Architectural Glass: Eight Contemporary Extensions That Redefine Indoor-Outdoor Living
The boundary between inside and outside has never been more beautifully blurred.
20 min read
UK-Wide
Biophilic Design
Key Facts at a Glance
This is not about conservatories. Modern architectural glazing combines structural innovation with thermal performance that meets or exceeds Building Regulations, creating year-round living spaces.
Average frameless glass box: Around £40,000. Costs range from £14,000 (small) to £80,000+ (large architectural projects).
Property value impact: Up to 7% increase—outperforming brick extensions (6%) and conservatories (5%).
40+ years lifespan with standard maintenance. Quality installations are built to last.
£40k
Average frameless glass room cost
+7%
Property value increase potential
4m+
Glass panel heights now possible
40yrs
Expected lifespan with maintenance
Across the UK, homeowners are discovering that the most transformative addition they can make to their property is not more brick, more stone, or more timber—but more light. Contemporary glass extensions have evolved from architectural curiosity to design necessity, creating spaces that feel simultaneously protected and exposed, intimate yet expansive, thoroughly modern yet timelessly elegant.
Understanding Contemporary Glass Extensions
Before exploring inspiring design approaches, it helps to understand the different types of glass extension. The terminology can be confusing, but the distinctions matter when planning your project.
Frameless Glass Box
The purest expression. Structural glass panels connected by nearly invisible silicone joints. Completely unobstructed views with glass bearing structural loads.
Framed Glass
Slim aluminium or steel profiles support glass panels. Modern frames achieve sightlines of just 17-21mm. More flexibility for opening elements.
Hybrid Glass
Combines glass with other materials—solid insulated roof with floor-to-ceiling glass walls. Often suits period properties beautifully.
The design options for a glass box extension are endless. From a full glass box with clear glass on all sides, to the introduction of solid elements like a solid roof, a glass extension can be designed to suit your space. Unlike a conservatory, a contemporary frameless glass box extension aims to create a smooth transition to the outside with full glazing, providing unobstructed views.
2025 Trend: Oversized Glass Panels
One of the biggest trends for 2025 is the use of oversized glass panels in both commercial and residential architecture. These panels create expansive views, increase natural light, and deliver a sense of openness that resonates with contemporary design preferences. According to a recent industry report, the oversized glass panel trend is expected to continue growing in 2024 and beyond, with manufacturers investing in new technologies to produce even larger panels.
Where once glass panels were measured in centimetres, today’s installations regularly exceed four metres in height, creating dramatic interior spaces that transform the relationship between home and garden.
Eight Inspiring Design Approaches
These eight approaches illustrate the breadth of possibilities when working with architectural glass. Each represents a different philosophy of how glass can transform residential space.
1
The Invisible Addition
Using frameless structural glass with silicone-bonded joints, these additions create the impression that interior space simply flows outward without interruption. The glass disappears entirely on clear days. Works exceptionally well with mature gardens and exceptional views.
2
The Period Property Contrast
When glass meets a Victorian or Georgian facade, rather than competing, the transparency allows the historic building to remain the visual focus. Black-framed glass against warm London stock brick creates a confident dialogue between old and new.
3
The Side Return Transformation
Victorian and Edwardian terraces often have narrow side returns—some of the most valuable square footage in residential property. Glass side returns unite previously separate spaces, with costs around £2,000/m² plus £40,000 for complete projects.
4
The Wraparound Glass Room
For corner positions or generous plots, L-shaped or U-shaped additions provide panoramic views that change character throughout the day. Morning light from one direction, afternoon sun from another—the relationship becomes dynamic.
5
The Glass Link
Glass links connect existing structures while maintaining visual separation—covered walkways that feel like being outdoors. Perfect for connecting main houses to converted garages, annexes, or garden studios.
6
The Oriel Window Room
Glass oriel windows cantilever from building facades to create frameless viewing spaces without extensive groundworks. Ideal for bedrooms seeking borrowed light or studies requiring inspiring views without sacrificing wall space.
7
The Glass and Timber Hybrid
Combining glass with natural materials creates warmth that pure glazing cannot achieve alone. Exposed Douglas Fir or oak provides visual warmth while frameless glass corners wrap around key vantage points. Suits rural properties beautifully.
8
The Industrial Aesthetic
Steel-framed glazing systems replicate classic industrial structures with contemporary design sensibilities. The grid of mullions provides rhythm and scale. Modern steel-look systems offer this aesthetic without thermal penalties.
The Science of Light and Wellbeing
The appeal of glass extensions goes beyond aesthetics. A growing body of research suggests that exposure to natural light and visual connections with nature provide measurable benefits to physical and mental health—a concept now central to biophilic design.
The Biophilic Connection
Biophilia, from the Greek words meaning “love of life,” describes humanity’s innate need to connect with nature and living things. Glass is uniquely suited to biophilic design. As a building material, glass can help support interior plant life, increase natural views and daylighting for occupant satisfaction, and improve energy efficiency to support sustainability goals.
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Reduced stress through nature connection
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Enhanced creativity and clarity of thought
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Improved wellbeing and mental health
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Better sleep through circadian rhythm regulation
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Increased productivity at home
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Brain stimulation from dynamic light scenes
The changing quality of light through a glass extension—from morning brightness through afternoon warmth to evening glow—provides exactly the kind of natural variation our brains have evolved to expect.
Technical Considerations
The beauty of contemporary glass extensions depends entirely on solving practical challenges that once made all-glass structures problematic. Understanding these considerations helps distinguish well-engineered projects from those that will disappoint.
Thermal Performance and U-Values
The thermal performance of glazing is measured by its U-value: the rate at which heat transfers through the glass. Lower U-values indicate better insulation. Building Regulations require extensions achieve 1.6 W/m²K or better.
Modern high-performance glazing routinely achieves 1.1-1.2 W/m²K
The most advanced systems reach 0.8 W/m²K or better
Some manufacturers now offer vacuum insulating glass achieving 0.17 W/m²K
⚠️ Compare Like With Like
Always ensure you’re comparing Uw values (whole window performance including frames) rather than Ug values (centre pane only). Some suppliers quote Ug values, which are always more impressive than actual installed performance.
Solar Control and Overheating
The historical criticism of conservatories—unbearably hot in summer, cold in winter—remains relevant for glass extensions. Solving this requires careful attention to solar control measures.
Solar control coatings prevent infrared rays entering while retaining warmth
Smart glass (electrochromic) can transition between transparent and tinted states automatically
SHGC (Solar Heat Gain Coefficient) measures how much solar radiation converts to heat—lower is better for south/west-facing extensions
Investment and Value: Understanding Costs
Glass extensions represent significant investments, but they also deliver substantial returns both in property value and daily living experience. Understanding the cost structure helps ensure realistic budgeting.
Extension Type
Typical Cost Range
Small glass extension
£14,000 to £30,000
Frameless glass box (average)
£40,000 to £60,000
Large architectural extension
£60,000 to £100,000+
Glass side return extension
£2,000/m² + £40,000
High-performance specification
£3,500+ per m²
Professional cleaning service
£150 to £400 annually
Small Glass Extension
Typical Cost Range£14,000 to £30,000
Frameless Glass Box (Average)
Typical Cost Range£40,000 to £60,000
Large Architectural Extension
Typical Cost Range£60,000 to £100,000+
Glass Side Return Extension
Typical Cost Range£2,000/m² + £40,000
High-Performance Specification
Typical Cost Range£3,500+ per m²
Property Value Impact
High-quality glass extensions can increase property value by up to 7%, comparing favourably with brick-built kitchen extensions (around 6%) and traditional conservatories (approximately 5%). According to Nationwide, home improvements that add additional floor area can increase property values by up to 25% in optimal circumstances.
Factors Affecting Cost
Glass specification: Solar control coatings, heated glass, and triple glazing all add cost but improve performance
Frame material: Aluminium costs less than steel; frameless structural systems command premium prices
Location: Building costs significantly higher in London and the South East
Site access: Difficult access requiring specialist equipment or crane hire increases costs substantially
Planning and Design Considerations
Creating a successful glass extension involves more than selecting beautiful glazing. The design process must address practical, regulatory, and aesthetic considerations that determine whether the finished structure enhances or compromises your home.
Working with Professionals
Glass extensions demand specialist expertise. These types of extensions are a costly exercise and you will still need to adhere to ever stricter Building Regulations. You should definitely work with a qualified architect and structural engineer rather than attempting to design complex glazing installations independently.
Planning Permission
Just as with any kind of extension, there will be cases where planning permission might not be required. Extensions can sometimes be built under permitted development if they don’t exceed specific parameters. However, even if you feel certain your extension falls within permitted development rights, always check with your local planning authority.
Heritage & Conservation
If you’re extending a listed building, live in a Conservation Area, or occupy an Area of Outstanding Natural Beauty, you will almost certainly require planning permission or listed building consent. Glass extensions to heritage properties often require particularly careful justification—though their transparent nature can sometimes help secure approval.
Orientation and Solar Gain
South-facing: Require careful solar control to prevent overheating
North-facing: Need high-performance glazing to maintain warmth without direct solar gain
East-facing: Capture morning light—ideal for breakfast rooms or home offices
West-facing: Enjoy afternoon and evening sun—perfect for entertaining spaces
Is a Glass Extension Right for You?
Glass extensions suit properties and homeowners seeking particular outcomes. Understanding what these structures do best helps determine whether this approach matches your aspirations.
Glass Extensions Excel When You Want:
✓ Maximum natural light penetration into previously dark spaces
✓ Seamless visual connection between interior and garden
✓ A contemporary addition that respects period architecture
✓ Biophilic benefits of nature connection for health and wellbeing
✓ Year-round enjoyment of garden views regardless of weather
✓ A statement addition that differentiates your property in the market
✓ Space that feels larger than its physical footprint
Consider Alternatives When:
• Privacy from neighbours is a primary concern
• Budget is severely constrained
• The site lacks attractive views worth framing
• You prefer enclosed spaces to open, light-filled rooms
• Access for cleaning and maintenance would be impractical
Bringing Light Into Your Life
Contemporary glass extensions represent more than architectural fashion. They respond to fundamental human needs: for light, for connection to nature, for spaces that inspire and restore. The technology that makes these structures possible continues to advance, with thermal performance, solar control, and structural capabilities improving year on year.
Whether your dream involves a frameless glass box that makes architecture disappear, a bold steel-framed structure that celebrates its engineering, or a sensitive hybrid design that bridges old and new, the range of possibilities has never been greater.
The eight approaches explored in this article represent starting points rather than limitations. Every successful glass extension is bespoke, designed to respond to its specific site, its owners’ aspirations, and its architectural context. To explore what a contemporary glass extension might mean for your home, discover our contemporary frameless glass box extension services and begin imagining your own transformation.
The boundary between inside and outside awaits your imagination.
Frequently Asked Questions
How much does a glass box extension cost?
Glass box extensions typically cost from £14,000 for small structures to over £80,000 for large architectural projects. The average frameless glass room costs around £40,000. Expect to pay approximately £3,000 per m² for glazing, with high-performance specifications reaching £3,500 or more per m².
Will a glass extension overheat in summer?
Modern glass extensions incorporate solar control coatings and high-performance glazing that prevent overheating. Smart glass technology can automatically adjust tinting in response to sunlight. Proper specification ensures comfortable temperatures year-round, unlike the conservatories of previous decades.
Do glass extensions add value to property?
Quality glass extensions can increase property value by up to 7%, outperforming both traditional brick extensions (6%) and conservatories (5%). Beyond financial return, they provide immediate lifestyle value through year-round usable space flooded with natural light.
Can glass extensions be built on period properties?
Yes, glass extensions often suit period properties exceptionally well. The transparency allows the original architecture to remain visible and dominant. The clear contrast between old and new can actually help secure planning approval by demonstrating respect for historic fabric.
What is the difference between framed and frameless?
Frameless extensions use structural glass panels connected by nearly invisible silicone joints, creating completely unobstructed views. Framed systems use slim aluminium or steel profiles, some with sightlines as narrow as 17mm. Choice depends on budget, aesthetic preference, and need for opening elements.
What U-values should a glass extension achieve?
Building Regulations require U-values of 1.6 W/m²K or better for extensions. High-performance glazing systems routinely achieve 1.1-1.2 W/m²K, with the most advanced reaching 0.8 W/m²K or better. Always ensure you’re comparing whole-window (Uw) values rather than centre-pane (Ug) values.
Do I need planning permission?
Some glass extensions fall within permitted development rights, but this depends on size, position, and location. Listed buildings, Conservation Areas, and Areas of Outstanding Natural Beauty almost always require planning permission. Always check with your local planning authority before proceeding.
How long do glass extensions last?
Quality glass extensions built with high-grade aluminium frames and properly specified glazing typically last 40 years or more with standard maintenance. The glass itself is extremely durable, while structural silicone joints may require eventual replacement after 20-25 years.
What maintenance do glass extensions require?
Glass extensions require regular cleaning to maintain appearance, typically costing £150-£400 annually for professional services. Low-maintenance coatings reduce cleaning frequency. Aluminium frames require minimal attention, while seals and drainage should be inspected periodically.
Can any builder install a glass extension?
Glass extensions require specialist skills and experience. The structural engineering, precision installation, and weatherproofing of large glass panels demand expertise that general builders may not possess. Working with specialist glazing companies ensures proper installation and valid warranties.
What is biophilic design and why does it matter?
Biophilic design recognises humanity’s innate need to connect with nature. Research shows that spaces with natural light and views of nature reduce stress, enhance creativity, improve wellbeing, and expedite healing. Glass extensions deliver these benefits by creating strong visual connections with the natural world.
What is the largest glass panel that can be installed?
Modern structural glazing systems can accommodate panels exceeding four metres in height, with some installations reaching even larger dimensions. The practical limit depends on access for delivery, crane hire requirements, and structural support. Larger panels generally require specialist installation equipment.
Can glass roofs be walked on?
Walk-on glass floors and rooflights are engineered specifically for foot traffic, using multiple layers of toughened and laminated glass. Standard roof glazing is not designed to be walked on. If maintenance access is required, this must be specified during design to ensure appropriate glass selection.
What happens if glass panels crack or fail?
Structural glass uses toughened and laminated glass designed to fail safely. Laminated panels remain intact even when cracked, held together by interlayer films. Quality installations include designs that allow individual panel replacement without dismantling entire structures.
Ready to Blur the Boundary Between Inside and Outside?
West Sussex Glass Extensions: Design Lessons from the South Downs | Room Outside
🏔️ South Downs Design Guide
West Sussex’s Most Distinctive Glass Extensions
How the best architects create glass rooms that honour Sussex’s vernacular heritage while bringing homes into the 21st century.
22 min read
West Sussex
South Downs National Park
The West Sussex Advantage
Property values here support significant investment. With average prices exceeding £435,000 county-wide and prime areas commanding much more, quality glass extensions deliver strong returns.
5-15% value added by well-designed glass extensions according to local estate agents.
National Park restrictions aren’t obstacles—they’re frameworks that produce better architecture when designers treat them as creative prompts.
The best extensions don’t fight heritage. They enter into a conversation with it, creating something that feels both ancient and entirely modern.
£435k+
Average West Sussex property price
5-15%
Property value added by quality glass rooms
30%
Max floor area increase in National Park
£680k
Average detached home price
There is something about the light in West Sussex that makes glass architecture sing. Perhaps it is the way the chalk downland reflects the sky, or the soft coastal haze that filters the afternoon sun. Whatever the reason, glass extensions here have a quality you do not find elsewhere.
The West Sussex Context: Why Location Shapes Everything
West Sussex presents designers with a particular set of opportunities and constraints. The county encompasses some of England’s most protected landscapes, from the rolling chalk downs to the ancient woodland of the Weald. Property values here reflect both the beauty and the scarcity of development opportunity.
Much of the county falls within or adjacent to the South Downs National Park, designated in 2010 for its outstanding natural beauty. According to the South Downs National Park Authority, planning within the park boundary requires heightened design sensitivity. Extensions must demonstrate they will not harm the landscape character, and extended permitted development rights do not apply within National Park boundaries.
This is not an obstacle to good design. It is a framework that, when embraced, produces better architecture. The most successful glass extensions in West Sussex are those where designers have treated the planning constraints as creative prompts rather than bureaucratic hurdles.
The Material Palette of Sussex
To understand how glass extensions succeed in this landscape, you first need to understand the materials they sit alongside. Historic England’s research documents how Sussex buildings evolved from what could be found locally: oak and clay in the Weald, flint and brick along the Downs, tile hanging where weather protection was needed.
Flint is the signature material of the chalk downland. The dark, glassy centres of knapped flint create surfaces that catch and reflect light in ways that glass naturally complements. There is an affinity between these materials that skilled designers exploit.
Brick comes in distinctive Sussex colours, from the soft reds of the Weald to the yellower tones nearer the coast. Tile hanging, originally practical against driving rain, has become decorative tradition. Understanding these materials shapes how a glass extension should be detailed, positioned, and proportioned.
Design Lessons from Successful Projects
The finest glass extensions in West Sussex share certain principles, even when they look quite different from one another. These are observations drawn from projects that have earned both planning approval and the admiration of those who live in and around them.
1
Acknowledge the Hierarchy
The original building should remain the dominant presence. This doesn’t mean glass extensions must be small or apologetic—it means they should defer to the host building in ridge height, visual mass, and presence from the street. The best designs are confident without being assertive.
2
Choose Your Frame Language Carefully
The frame system makes a design statement whether you intend it or not. Slim aluminium profiles suggest contemporary sensibility. Painted timber with glazing bars references tradition. Neither is inherently better, but each says something different about the relationship between old and new.
3
Think About Roofscape
In hilly terrain like the Downs, buildings are often seen from above. A glass roof that looks elegant from inside can appear as a blank reflective panel from uphill neighbours. The best designs consider this, using roof profiles that slope away from sightlines or elements that break up reflection.
4
Consider the Garden and Beyond
A glass extension exists in relationship with its garden, boundaries, and often the wider landscape. The most thoughtful designs treat the garden as part of the architectural composition. Planting softens boundaries, hard landscaping connects to the house palette, and positioning maximises borrowed views.
Planning Officers Respond Positively To…
In villages within the National Park, we’ve seen planning officers respond positively to designs that use slender steel frames echoing traditional orangery proportions. The material reads as clearly contemporary, but the rhythm and proportions connect to the Georgian and Victorian glasshouse tradition. This is not pastiche—it’s an intelligent acknowledgment of context.
Orangeries and Glass Boxes: Different Solutions for Different Houses
Two distinct typologies dominate the high-end glass extension market in West Sussex: the contemporary glass box and the modern orangery. Both can be exceptional. Both can be appropriate in the right context. Understanding which suits your property is fundamental to achieving an outstanding result.
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Contemporary Glass Box
Pure glass boxes work best where contrast is the design intention. Against a robust Victorian villa, a minimal glass volume creates deliberate tension between historic substance and contemporary transparency. Requires exceptional glazing quality and precise junction detailing.
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Modern Orangery
Solid perimeter wall topped by glazing with a lantern roof. Often receives warmer planning responses due to historical precedent. Can incorporate matching brickwork extending the host building’s material language. Better thermal performance with less reliance on heating/cooling.
🔗
Glazed Link
Connecting new additions to period buildings or linking main house to outbuildings. Often required by planners for listed building extensions. Provides clear separation between old and new, allowing each to be read distinctly.
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Garden Room
Suits all property types where additional space at garden level is the priority. Can be freestanding or attached. May fall under permitted development if not attached. Larger or attached versions usually require planning permission.
Navigating West Sussex Planning: A Practical Guide
Planning regulations in West Sussex vary significantly depending on your specific location. Understanding which rules apply to your property is essential before investing in design development.
Within the South Downs National Park
If your property falls within the National Park boundary, permitted development rights are significantly restricted. Most extensions require planning permission, even relatively modest ones. The South Downs National Park Authority operates its own planning service with policies specifically designed to protect the special qualities of the landscape.
Extensions to small and medium houses generally limited to approximately 30% increase in gross internal floor area
Every application assessed for impact on local character and appearance
Meeting size thresholds does not guarantee approval if design is considered harmful
Dark skies are actively protected—roof glazing that emits light upward faces additional scrutiny
⚠️ Dark Sky Protection
The South Downs is an International Dark Sky Reserve. This affects glazed extension design, particularly roof glazing that could emit light upward. Designs that manage internal lighting spillage and avoid sky glow perform better in the planning process.
Outside the National Park
Properties outside the National Park but still in West Sussex typically have access to standard permitted development rights, though conservation areas impose additional constraints. The local planning authorities covering West Sussex include Chichester, Horsham, Mid Sussex, Crawley, Arun, Adur, and Worthing, each with their own local plan and design guidance.
Even where permitted development applies, glass extensions often exceed the parameters for exempt development. Rear extensions beyond certain depths, side extensions, and roof additions all require careful assessment against specific permitted development rules.
Glass Extension Types at a Glance
This comparison shows the key characteristics of different glass extension approaches for West Sussex properties.
Type
Best Suited To
Planning Considerations
Frameless Glass Box
Victorian/Edwardian villas, substantial brick or stone houses where contrast is desirable
Often approved when positioned away from principal elevations. Conservation areas may require design statements.
Modern Orangery
Georgian/Regency properties, listed buildings, houses in conservation areas
Generally well received due to historical precedent. Can use matching materials.
Glazed Link
Connecting additions to period buildings, linking house to outbuildings
Often required by planners for listed building extensions. Provides clear old/new separation.
Garden Room
All property types where additional garden-level space is priority
May fall under PD if not attached. Larger/attached versions usually require permission.
Frameless Glass Box
Best Suited ToVictorian/Edwardian villas, substantial brick or stone houses where contrast is desirable
Planning ConsiderationsOften approved when positioned away from principal elevations. Conservation areas may require design statements.
Modern Orangery
Best Suited ToGeorgian/Regency properties, listed buildings, houses in conservation areas
Planning ConsiderationsGenerally well received due to historical precedent. Can use matching materials. ✓ Best planning response
Glazed Link
Best Suited ToConnecting additions to period buildings, linking house to outbuildings
Planning ConsiderationsOften required by planners for listed building extensions. Provides clear old/new separation.
Garden Room
Best Suited ToAll property types where additional garden-level space is priority
Planning ConsiderationsMay fall under PD if not attached. Larger/attached versions usually require permission.
Making the Investment Work: Property Value Considerations
West Sussex property prices support significant investment in quality extensions. With detached homes averaging around £680,000 across the county and premium areas commanding substantially more, a well-designed glass room that adds genuine living space typically delivers strong returns.
The economics work differently at different price points. For a £500,000 property, a £60,000 glass extension needs to add meaningful value to justify itself. Evidence from estate agents suggests that well-designed garden rooms and glass extensions can add 5-15% to property value in this area. At £500,000, that represents £25,000 to £75,000 of value for your investment.
What Drives Value in This Market
Estate agents in West Sussex consistently report that buyers respond most strongly to glass extensions that achieve these qualities:
Year-round usability through proper thermal specification
Seamless connection to garden space
Natural light flooding into the main house
Design quality that enhances rather than compromises the original building
Materials and finishes that will age gracefully
The Value Calculation
On a £500,000 property, a quality glass extension adding 5-15% value represents £25,000-£75,000 of added value. With typical costs of £50,000-£90,000 for a 25 sqm glass box, the investment often pays for itself while dramatically improving how you live.
But the calculation shouldn’t be purely financial. A glass extension that allows your family to use your home differently—to connect inside and outside, to have space for activities that currently can’t happen—delivers value that doesn’t appear on balance sheets.
Working with the West Sussex Landscape
For homeowners across West Sussex and the surrounding areas, the landscape offers both inspiration and responsibility. The rolling downland, the ancient woodlands, the coastal light—all these qualities draw people to live here. Good architecture responds to these qualities and contributes to them.
Orientation and Light
The quality of light in this part of England is particularly suited to glass architecture. The relatively high proportion of diffuse light, filtered through the maritime atmosphere, creates soft illumination that glass rooms capture beautifully. South facing extensions benefit from direct sun in winter when it’s welcome, while proper specification manages summer heat gain.
North facing glass rooms have their own appeal, offering even, consistent light throughout the day. Artists and photographers often prefer this quality, and dining rooms used primarily in the evenings work well without direct sun.
Views and Framing
Many West Sussex properties enjoy views toward the Downs, across farmland, or through woodland. A glass extension offers the opportunity to frame these views as deliberate compositions. The position of structural elements, the height of sills, the proportion of openings—all shape how the landscape is experienced from inside.
Some of the most successful designs use glass sparingly on sides with less attractive outlooks, concentrating transparency where views reward it. This selective approach often performs better architecturally than all-glass solutions that treat every direction equally.
Creating Something That Belongs
The most distinctive glass extensions in West Sussex share a quality that is easier to recognise than to describe. They look like they belong. Not because they copy what surrounds them, but because they respond to it with intelligence and care.
This is architecture that understands its context, whether that context is a flint cottage in a National Park village or a substantial Victorian house in a Horsham conservation area. It takes the constraints seriously and finds creative solutions within them. It respects what came before while making a clear statement about now.
The Bottom Line
If you’re considering a glass extension in West Sussex, take time to look at what already surrounds your property. Notice the materials, the proportions, the way light falls at different times of day. Think about how you want to live in the new space and how it will connect to your garden and your views.
Then find designers and builders who share your ambition to create something that will still look right in twenty years, in fifty years. Something that future owners will be grateful you built. Explore our glass room designs or contact us to discuss what might be possible for your property.
Frequently Asked Questions
Do I need planning permission for a glass extension in West Sussex?
It depends on your location and the size of the extension. Properties within the South Downs National Park have restricted permitted development rights, meaning most extensions require planning permission regardless of size. Outside the National Park, standard permitted development rules apply, but glass extensions often exceed exempt parameters.
What are the planning restrictions in the South Downs National Park?
Extensions to small and medium houses are generally limited to approximately 30% increase in gross internal floor area. All applications are assessed for impact on local character. Dark sky protection means designs that emit light upward face additional scrutiny. Pre-application advice is strongly recommended.
How much does a high-quality glass extension cost?
Quality glass extensions typically cost £2,000-£3,500 per square metre. A 25 sqm glass box might range from £50,000-£90,000. A substantial orangery with high-specification glazing could range from £75,000-£150,000 or more depending on specification and site conditions.
Will a glass extension add value to my property?
Evidence from local estate agents suggests well-designed glass extensions typically add 5-15% to property value. On a £500,000 property, that represents £25,000-£75,000 of added value. The key qualifiers are ‘well-designed’ and ‘well-executed’.
What is the difference between an orangery and a glass box?
An orangery has a solid perimeter wall topped by glazing with a lantern roof, creating a more enclosed room. A glass box uses minimal framing and maximum glazing for the most transparent structure. Orangeries often receive warmer planning responses in conservation areas due to historical precedent.
Can I build a glass extension on a listed building?
Yes, but you will need listed building consent as well as planning permission. Contemporary glass designs can work well on listed buildings when clearly differentiated from historic fabric while respecting its character. Glazed links that create separation between old and new are often favoured.
How long does it take to build a glass extension?
Allow approximately 3-4 months from planning approval to completion for a straightforward project. The planning process typically takes 8 weeks for standard applications, though National Park applications can take longer. Design development might take 2-4 months depending on complexity.
What U-values should I specify?
Building Regulations require windows to achieve a maximum U-value of 1.4 W/m²K, but for genuine year-round comfort, aim for 1.2 W/m²K or better. Triple glazing can achieve values of 0.8-1.0 W/m²K. The extra investment pays back through lower heating costs and year-round usability.
Is it possible to have a glass extension that doesn’t overheat?
Absolutely, but it requires thoughtful specification. Solar control glazing reduces heat gain, proper ventilation allows hot air to escape, and external shading is more effective than internal blinds. North facing glass rooms rarely overheat. South and west facing extensions need more careful management.
What frame materials work best?
Aluminium with thermal breaks offers slimmest sightlines and best durability. Steel provides even slimmer profiles with an industrial aesthetic. Timber offers warmth and traditional appeal but requires more maintenance. The choice depends on the look you want, budget, and maintenance commitment.
Can I use my existing conservatory footprint?
Often yes, though you may need to replace foundations if the existing base is inadequate for the new structure’s weight. Using an existing footprint can simplify planning, particularly if not increasing overall size. However, you may still need permission if exemptions no longer apply.
Do I need Building Regulations approval?
Most glass extensions require Building Regulations approval, separate from planning permission. The regulations cover structural safety, thermal performance, and ventilation. Some small conservatories are exempt if meeting specific criteria including separation from the main house by external quality doors.
What maintenance does a glass extension require?
Glass requires regular cleaning, more frequently than you might expect for maintaining transparency. Frames need periodic checking and may need repainting or resealing depending on material. Seals and gaskets may need replacement after 10-15 years. None is onerous, but budget time and money for ongoing care.
Can you help with glass extensions across West Sussex?
Yes. We work with homeowners throughout West Sussex, from Chichester to Crawley, from coastal towns to villages of the Downs and Weald. We understand the specific planning contexts, local architectural character, and expectations of both planners and buyers in this area.
Bespoke Conservatory Design: Creating Spaces That Transform How You Live
Learn what genuine bespoke design means, why New Generation Glass creates conservatories you’ll love year-round, and how to find true specialists who protect your investment.
25 min read
South East England
50+ Years Expertise
Quick Answer
True bespoke conservatory design means creating an architectural masterpiece engineered specifically for your property using premium materials like hardwood or aluminium, advanced temperature-control glazing such as New Generation Glass, and individual design that respects your home’s character. The difference between bespoke design and standard conservatories isn’t just quality; it’s the difference between a space you’ll treasure for generations and one you’ll tolerate for a decade.
For over 50 years, Room Outside, based in West Sussex, has been designing and building luxury bespoke conservatories, orangeries and glass extensions across the South East of England, including Surrey, Hampshire, Sussex, Kent and Greater London. That experience means we know exactly what works for UK homes and UK weather.
Stand in any beautifully designed conservatory on a crisp January morning, sunlight streaming through perfectly engineered glass, warmth enveloping you despite the frost outside. This isn’t luck. It’s not even expensive heating. It’s what happens when genuine architectural expertise meets advanced glazing technology.
Yet most UK homeowners will never experience this. They’ll settle for spaces that feel like greenhouses in July and ice boxes in December, wondering why their £20,000 investment only gets used six months of the year.
The difference? Understanding what “bespoke” actually means, and why it matters far more than most conservatory companies will ever admit.
Why Most “Bespoke” Conservatories Aren’t Actually Bespoke At All
Walk into most conservatory showrooms and you’ll hear the word “bespoke” within the first five minutes. They’ll show you Victorian styles, Edwardian options, perhaps a contemporary lean-to. You’ll pick your size from a measuring tape, your colour from a chart, maybe some decorative glazing bars from a catalogue.
They’ll call this “bespoke.”
It isn’t.
What’s really happening: You’re selecting from pre-engineered modular systems, choosing options like ordering from a menu. Made-to-measure? Yes. Custom colours and features? Certainly. But individually designed for your specific property’s architecture, orientation, and your lifestyle? Not remotely.
The Suit Analogy
Think of it like buying a suit. Most high street shops offer “made-to-measure” services. They’ll adjust standard patterns for your measurements, perhaps offer fabric choices. That’s what most conservatory companies provide.
True bespoke is what happens when a master tailor studies your build, your posture, how you move, what you’ll wear it for, and creates something that exists nowhere else in the world. Every seam, every dart, every detail considered specifically for you.
That’s the difference we’re talking about with conservatory design.
The Three Critical Elements That Define Genuine Bespoke Design
Room Outside brings over 50 years of expertise to the art of designing and building bespoke glass extensions, creating structures that blend timeless elegance with innovative functionality.
Real bespoke design begins with architectural analysis. The designer studies your property like an art historian examining a painting. What period is it? What are the proportions telling us? How do the roof lines interact? What’s the rhythm of the windows? What materials create the character?
Then they look at you. How do you live? When do you use spaces? Do you entertain? Work from home? Have small children or grandchildren visiting? Love gardening? Read for hours? Cook elaborate meals?
Only then does design begin. Not selecting from templates, but creating something unique that:
Respects your property’s architectural DNA
Enhances rather than compromises its character
Works specifically for your lifestyle patterns
Responds to your site’s unique orientation and microclimate
Creates proportions and rhythms that feel inevitable, as if it was always meant to be there
The tell-tale sign you’re not getting bespoke design: The conversation focuses on style selection (“Victorian or Edwardian?”) rather than architectural analysis of your specific property.
2. Advanced Glazing Technology (Not Just “Energy-Efficient” Glass)
Here’s where most conservatory companies lose the plot entirely. They’ll talk about “energy-efficient glass” or “solar control glazing” as if it’s all basically the same thing with minor variations.
It categorically isn’t.
Standard double glazing insulates. That’s useful, but it doesn’t solve the fundamental problem: glass conducts temperature. Traditional conservatories experience wild temperature swings because the glass transmits solar heat in summer and radiates heat out in winter.
Room Outside pioneered the introduction of New Generation Glass from the USA over 20 years ago, further developing it to suit the British climate, enabling structures that provide unmatched comfort and usability all year round.
Advanced temperature-control glazing like New Generation Glass does something entirely different. It actively manages solar radiation, selectively filtering wavelengths that create heat whilst maintaining visible light transmission. It’s not just thicker or better insulated; it’s fundamentally different technology.
What This Means in Practice
Summer afternoon, blazing sunshine: your neighbour’s conservatory reads 38°C and is unusable. Yours? A comfortable 23°C. No air conditioning. No giant fans. Just intelligent glazing working exactly as engineered.
January evening, frost forming outside: you’re sitting in your conservatory reading without a jumper because the combination of advanced glazing and modest heating creates comfortable, stable temperatures that traditional conservatories simply cannot achieve regardless of how much you spend heating them.
15-25°C
Temperature variation with standard conservatory
5-8°C
Temperature variation with advanced glazing
20+ yrs
UK development of New Generation Glass
That’s not marginal improvement. That’s the difference between a space you occasionally tolerate and one you genuinely live in daily.
The tell-tale sign you’re not getting advanced glazing: They talk about glass thickness and insulation but can’t explain how solar heat gain is actively managed or provide specific performance data for your orientation.
Premium aluminium: Custom extrusions, ultra-fine sightlines (as low as 20mm), exceptional strength for larger glass spans
Visual Character
uPVC: Always looks like uPVC, regardless of colour or woodgrain effects
Hardwood: Warmth, depth, grain character that improves with age
Premium aluminium: Clean, precise, contemporary aesthetic impossible with other materials
For properties where architectural integrity matters, material selection isn’t about budget. It’s about whether the conservatory enhances or compromises your property’s character for the next half-century.
The tell-tale sign you’re not getting premium materials: The conversation focuses primarily on uPVC with hardwood positioned as an expensive upgrade rather than the appropriate choice for your property’s architectural quality.
What’s the Difference Between an Orangery, a Conservatory and a Glass Extension?
Quick Answer
An orangery is a more solid, room-like structure with brick or stone pillars and a solid roof with a central lantern. A conservatory is usually more than 75% glass in the roof and walls, with a lighter, more transparent feel. A glass extension is a fully integrated building extension that moves the home’s thermal envelope, meeting much higher insulation standards than a traditional conservatory.
What Makes an Orangery Different (And Why It Matters)
Orangeries have a solid roof with less than 75% glazing and feature substantial masonry construction with brick or stone pillars, creating more solid structure than conservatories which typically have over 75% roof glazing.
Think of orangeries as proper rooms with exceptional natural light rather than glass structures with some solid elements.
The solid roof perimeter creates an internal plastered pelmet running around the room’s edge. This provides:
Space for downlighting creating proper room ambiance (impossible with all-glass roofs)
Visual weight and enclosure making it feel like a room, not a greenhouse
Superior thermal performance through insulation mass
Architectural presence that brick or stone pillars reinforce
Walk into a well-designed orangery and you don’t think “conservatory.” You think “beautiful room with extraordinary light.”
When Orangeries Make Sense
You want proper room character, not indoor-outdoor transitional space
Year-round thermal comfort is non-negotiable
Your property’s architecture has sufficient presence
Extending kitchen or dining space where room character matters
Privacy from neighbours or overlooking is important
When Conservatories Work Better
Maximum connection to garden is priority
You love the light, transparent character of glass structures
Your property’s style suits lighter architectural language
You want that magical indoor-outdoor blurred boundary
Budget favours predominantly-glazed structures
Neither is inherently “better.” They’re different architectural responses to different requirements and properties.
Glass Extensions: The Contemporary Alternative That Changes Everything
A glass extension is a true building extension that’s fully open to the existing house. It moves the external thermal envelope, so it has to meet much higher insulation standards than a thermally separated glass conservatory with doors between the house and the structure.
The critical distinction: Building Regulations classify conservatories as thermally-separated structures (doors between conservatory and house). Glass extensions are fully-integrated, meaning they must meet full extension thermal performance standards.
What This Enables
Glass extensions can incorporate advanced technologies that conservatories often don’t:
Triple glazing as standard (U-values as low as 0.5 W/m²K)
Heated glass technology
Full integration with home heating systems
Contemporary architectural language
The Structural Glass Revolution
Contemporary frameless glass extensions use structural glass technology completely different from traditional conservatories. Laminated glass beams and fins create self-supporting structures with minimal visible framework. We’re talking 20-40mm ultra-fine profiles versus 100-150mm traditional conservatory frames.
Visual impact? Completely different. Where traditional conservatories have substantial framework creating that recognisable “conservatory” aesthetic, structural glass extensions achieve near-frameless transparency.
Why Premium Bespoke Orangeries Outperform Kit-Built Systems
The orangery market has exploded over the past decade. Unfortunately, so has confusion about what constitutes quality orangery design.
Most “orangery systems” offered by conservatory companies are pre-engineered modular kits with standard column spacing, predetermined lantern sizes, and generic architectural detailing. You’re selecting configurations, not commissioning design.
What Genuine Bespoke Orangery Design Delivers Differently
Architectural Integration
The designer studies your property’s existing architecture. If it’s Victorian, what are the typical Victorian orangery proportions? What column spacing and heights create appropriate rhythm? What cornice profiles and architectural details complement your existing mouldings?
If contemporary, how do we create an orangery interpretation that feels current rather than pastiche? What materials bridge traditional orangery form with modern architectural language?
This level of analysis simply doesn’t happen with kit systems.
Structural Sophistication
The insulated roof structure, column dimensions, load distribution, and foundation engineering are all designed specifically for your project’s requirements and soil conditions.
Kit systems use standardised engineering applied broadly. Usually adequate, but not optimised for your specific context.
Material Quality
True bespoke specialists offer luxury hardwood timber, aluminium, and masonry materials selected and specified specifically for each project, not predetermined system components.
The brickwork matches your property’s existing brick. The timber species, profiles, and finishes are selected for your architectural context. The lantern design is proportioned specifically for your orangery’s dimensions.
The Investment Perspective
Yes, genuinely bespoke orangery design requires substantially more investment than kit systems. But we’re talking about structures designed to enhance your property for 50+ years, not 20.
The question isn’t cost; it’s value over the genuine lifespan.
How Frameless Glass Extensions Differ From Everything Else
If you’ve only seen traditional conservatories, encountering a frameless glass extension is revelatory.
The fundamental difference: Instead of glass panels held in metal frames, structural glass units support themselves using laminated glass beams, glass fins, and structural silicone bonding. The glass is the structure.
This enables architectural possibilities impossible with conventional framing:
Corner glazing without vertical posts (uninterrupted 90-degree glass corners)
Cantilever sections
Asymmetric geometries
Continuous glass runs uninterrupted by visible framework
Walk into a frameless glass extension and the sensation is completely different from traditional conservatories. The transparency is extraordinary. Sightlines remain unbroken. Connection to landscape becomes immersive rather than merely visual.
When Frameless Glass Extensions Excel
Contemporary architectural aesthetic speaks to you
Maximum transparency is priority
Your property or project suits cutting-edge design
Garden or landscape has exceptional visual appeal
You want something architecturally distinctive
When Traditional Framing Works Better
Period property where contemporary materials feel inappropriate
Budget favours conventional construction
You prefer warmer visual character of timber frameworks
Traditional architectural language suits your property better
Neither approach is superior. They’re different architectural responses to different contexts and preferences.
The New Generation Glass Difference: Why 20 Years of UK Development Matters
Room Outside was the first company in England to introduce New Generation Glass from the USA over 20 years ago and further developed it to suit the British climate.
Let’s talk about what that actually means and why it matters for anyone considering a serious conservatory investment.
Standard “energy-efficient” glazing insulates. Multiple glass layers with gas-filled cavities reduce heat transfer. That’s useful, particularly for windows in solid walls.
But conservatories are predominantly glass. Insulation alone doesn’t solve the fundamental challenge: managing solar heat gain whilst maintaining transparency and insulation performance.
What Temperature-Control Glazing Does Differently
Sophisticated coatings applied to glass surfaces selectively filter solar radiation. Infrared wavelengths that create heat are reflected or absorbed, whilst visible light passes through relatively unimpeded.
The result: A conservatory roof can receive full summer sun without the interior becoming unbearably hot, because the heat component of sunlight is being filtered before it enters the space.
Why UK Climate Development Matters
USA and UK have fundamentally different climate challenges:
USA (particularly southern states): Extreme summer heat, solar gain management paramount
UK: Moderate summers but significant heating season, balance between solar control and heat retention crucial
Room Outside’s development of New Generation Glass for British climate means optimising this balance specifically for UK conditions:
Summer: Sufficient solar control to prevent overheating
Winter: Optimal light transmission and insulation to minimise heating requirements
Spring/Autumn: Passive solar heat gain that’s welcome, but controlled so the room doesn’t overheat
This climate-specific optimisation is why 20+ years of UK development matters. It’s not just licensing American technology; it’s adapting and refining it for genuinely different climate requirements.
How You Experience This
Your conservatory becomes a space you instinctively use year-round without thinking about temperature. No longer “should I turn the heating up?” or “it’s too hot in here.” Just comfortable space that works throughout the seasons.
That unconscious usability is the point. The best design becomes invisible; you simply live in beautiful, comfortable space without constantly managing its shortcomings.
What Truly Sets Bespoke Specialists Apart From Standard Conservatory Companies
After 50+ years in this industry, certain patterns become crystal clear about what distinguishes genuine specialists from companies offering standard products with “bespoke options.”
Operational Longevity Proves Sustained Excellence
Room Outside has spanned over 5 decades in business, offering expert experience designing and building bespoke glass extensions throughout the South East of England and further afield.
Half a century is a long time in any industry. Companies don’t achieve that longevity through marketing. They achieve it through:
Consistently delivering quality that generates referrals
Adapting to changing technologies whilst maintaining craft excellence
Building reputations that architects and construction professionals trust
Creating structures that still delight homeowners decades later
Why This Matters for You
When you invest in genuine bespoke design, you’re not just buying a structure. You’re starting a relationship with a company you’ll potentially work with again (repairs, maintenance, future projects) over decades.
Established specialists will still be there in 15 years when you want that roof panel replaced. They’ll still have craftspeople who understand their structures. Their reputation still depends on your satisfaction.
New entrants? Who knows.
Technology Leadership Versus Technology Following
Being the first company in England to introduce New Generation Glass over 20 years ago demonstrates genuine innovation leadership rather than following market trends.
Most conservatory companies adopt technologies once they’re mainstream and proven. Nothing wrong with that for standard products, but it reveals their market position.
True specialists invest in emerging technologies years before mainstream adoption. They develop relationships with innovative manufacturers globally. They’re willing to be pioneers because they’re genuinely focused on technical excellence, not just selling products.
Professional Specification Recognition
Award-winning Room Outside products have been specified for some of the most iconic buildings in the UK, earning an enviable reputation among the UK’s leading architectural practices and construction companies.
Architects and construction professionals don’t specify conservatory suppliers based on consumer advertising. They specify based on:
Technical competence and reliability
Quality consistency
Ability to deliver complex projects successfully
Responsiveness to design requirements
Problem-solving capability when challenges arise
Professional specification is the strongest indicator of genuine technical credibility.
Listed Building and Conservation Expertise
Specialists demonstrate capability across luxury hardwood timber, aluminium, and frameless glass extensions for grade one and grade two listed buildings and properties in National Parks and areas of outstanding natural beauty.
Securing Listed Building consent or planning approval in conservation areas requires:
Deep understanding of architectural heritage
Ability to design additions that conservation officers accept
Respect for historical architecture without pastiche
This expertise proves a level of architectural sophistication that standard conservatory companies rarely possess.
Even if your property isn’t listed: Companies with listed building expertise bring that same architectural sensitivity to all projects. They understand proportion, detail, materials, and integration in ways that benefit any property where quality matters.
Finding True Bespoke Conservatory Specialists: What to Look For
Most conservatory shopping focuses on wrong indicators. People compare prices across similar-seeming quotes, not realising they’re comparing fundamentally different quality levels.
The Design Consultation Reveals Everything
Quality designers work closely with clients from start to finish, exploring ideas and taking inspiration from the architecture of your home and your lifestyle.
In your first meeting, are they:
Studying your property’s architecture in detail?
Walking around examining roof lines, proportions, materials, existing architectural features?
Asking extensive questions about how you live, what matters to you, your long-term plans?
Or are they quickly measuring up and pulling out standard design catalogues?
The quality of that initial consultation tells you everything about whether you’re talking to a designer or a salesperson.
Portfolio Quality Over Portfolio Size
Don’t just count completed projects. Look at them critically:
Do the conservatories look architecturally integrated with their properties? Each should feel like it belongs, not like it was added. If everything looks similar regardless of property type, that’s a red flag.
Is there genuine design variety? You should see different architectural responses to different contexts. Similar-looking projects across different properties reveal predetermined solutions, not bespoke design.
Are there challenging projects? Listed buildings? Awkward sites? Unique architectural contexts? Complex requirements? These reveal problem-solving capability.
Technology Specificity Versus Generic Claims
“We use energy-efficient glass” means nothing. Every conservatory company says that.
What reveals genuine technology expertise:
Can they explain specific glazing specifications for your project?
Discuss U-values, solar heat gain coefficients, light transmission ratios?
Explain why they’d recommend particular glazing for your orientation and microclimate?
Articulate advanced systems like New Generation Glass and explain specifically how temperature-control glazing differs from standard insulation?
Generic descriptions like “keeps you cooler in summer and warmer in winter” are sales-speak. Technical specificity reveals genuine understanding.
Material Options Indicate Company Focus
If the conversation defaults to uPVC with hardwood positioned as expensive premium upgrade, that tells you where their focus lies.
Quality specialists discuss materials as architectural choices appropriate for different contexts, not budget tiers.
For many properties, hardwood is simply the right material regardless of cost. For contemporary projects, premium aluminium might be optimal. The conversation should be about what’s appropriate for your property and project, not what’s cheapest or most profitable.
Project Management Approach
True specialists take responsibility for planning and installation, providing complete peace of mind with comprehensive project management.
Who’s managing:
Planning applications if needed?
Building Regulations approval?
Foundation contractor coordination?
Construction timeline?
Problem resolution?
Final commissioning?
With quality specialists: They manage everything. Single point of accountability.
With component suppliers: You coordinate multiple contractors yourself.
The difference matters enormously for stress levels and ultimate quality.
The Questions That Reveal Everything
Want to know instantly whether you’re talking to genuine specialists? Ask these questions and pay attention to how they answer.
Ask These Before Committing
1. “How do you approach designing for properties like mine?”
Quality answer: Discusses architectural analysis, understanding your specific property’s character, how they develop individual design responses.
Red flag answer: Talks about selecting from their range of styles.
2. “What proportion of your projects are genuinely bespoke versus standard designs adapted by size?”
Quality answer: Honest about their focus. True specialists will say 80-100% genuinely individual design.
Red flag answer: Vague about the distinction or defensive about the question.
3. “What glazing would you specify for my project and why?”
Quality answer: Discusses specific technologies, your orientation, microclimate factors, performance expectations with technical specificity. Should mention advanced options like New Generation Glass.
Red flag answer: Generic “energy-efficient glass” without technical details.
4. “How long have you been designing and building bespoke conservatories specifically?”
Quality answer: 25+ years ideally, with consistent focus on quality glass extensions.
Red flag answer: Recent entrant or conservatories as recent addition to general building/windows business.
5. “Can you show me projects on listed buildings or in conservation areas?”
Red flag answer: Limited or no listed building experience.
6. “Who would design my conservatory and how does that process work?”
Quality answer: Named designer with architectural background, describes collaborative design development process.
Red flag answer: Vague about designer identity or process jumps from initial meeting to quotation without design development.
7. “Can you provide customer references for similar projects?”
Quality answer: Readily provides multiple contacts with similar property types and project scales.
Red flag answer: Reluctant to provide references or only offers vastly different project types.
Their comfort answering these questions tells you whether they’re confident in their expertise or hoping you won’t dig too deep.
Modern Design Ideas That Show What’s Possible in 2025
Let’s get specific about what exceptional bespoke design can achieve for different property types and lifestyle requirements.
Contemporary Side-Return Extensions for Urban Living
Victorian and Edwardian terraced houses throughout UK cities have narrow side-return spaces that traditionally house bins and bikes. Barely functional, often eyesores.
Clever glass extension design transforms these spaces into light-filled kitchen or living extensions that revolutionise how you use your ground floor.
Design approach: Full-height glazing on side elevation and rear, maximising light in inherently narrow, shaded positions. Flat glass roof carefully detailed to meet party wall and boundary constraints. Integration with large-span sliding doors opening to garden.
The challenge: Achieving comfortable thermal performance in highly-glazed urban positions where neighbouring properties limit ventilation.
Solution: Advanced solar control glazing preventing overheating, sophisticated artificial lighting design for evening use, careful ventilation strategy using automated rooflights.
Result: Previously wasted space becomes your favourite room. Natural light floods into previously dark side-return corridors. Kitchen expands into bright, usable space. Property value increases dramatically.
Structural Glass Boxes for Contemporary Properties
If your property’s architecture is contemporary or you’re adding contemporary extension to traditional home, frameless structural glass offers architectural possibilities unachievable with traditional conservatories.
Design concept: Glass beams and fins creating self-supporting structure with minimal visible framework. Corner glazing without vertical posts creates uninterrupted 90-degree glass corners. Ultra-fine profiles (20-30mm) appearing almost invisible.
Walk inside and the effect is extraordinary. Traditional conservatories, even nice ones, have framework interrupting sightlines. Structural glass extensions achieve near-transparency. It feels like inhabiting outdoor space whilst being comfortably protected.
Contemporary Orangeries with Clean Architectural Lines
Traditional Victorian or Georgian orangery styling feels wrong on many properties. But the orangery form itself—solid perimeter roof with central glazed lantern, brick or stone elements—remains architecturally excellent.
Modern interpretation: Clean-lined brick or rendered pillars without decorative mouldings. Flat super-insulated roof with contemporary aluminium lantern featuring minimal profiles. Floor-to-ceiling glazing between solid elements. Internal plastered pelmet providing downlighting locations.
Result: Orangery thermal comfort and room character without pastiche period styling. Works beautifully on contemporary properties or as clearly-contemporary addition to traditional homes. The visual language says “this is now” whilst respecting orangery architectural principles developed over centuries.
Garden Room Conservatories with Horizontal Emphasis
Traditional pitched-roof conservatory forms don’t suit every property or preference. Low-pitch or flat glass roofs create dramatically different aesthetic.
Design approach: Wide, low proportions emphasising horizontal lines rather than vertical pitch. Glass roof at 5-15 degrees or completely flat with concealed edge detailing. Large-span doors (4-6 metres) opening entire wall to garden.
Critical requirement: Excellent solar control glazing preventing overheating in low-pitch configurations. Standard glass in shallow-pitch roofs creates furnace conditions in summer.
Result: Contemporary garden room aesthetic distinct from traditional conservatory forms. Particularly appropriate for bungalows or single-storey extensions where restricted height requires low-pitch solutions.
Timber-Framed Extensions with Exposed Structure
For properties where natural materials and craft aesthetic matter, exposed hardwood timber structural framework creates warmth impossible with aluminium or uPVC.
Design concept: Substantial timber posts and beams (150-200mm sections) creating visible architectural structure. Timber rafters expressed internally rather than hidden. Large glass panels between timber framework. Natural timber finishes or contemporary painted colours.
Result: Architectural character and material warmth distinct from both ultra-minimal glass boxes and traditional conservatories. Particularly appropriate for rural properties, period homes where quality materials matter, or anyone who simply loves natural materials and visible craftsmanship.
Why Year-Round Comfort Matters More Than You Might Think
Here’s something most people don’t consider until it’s too late: conservatory usability determines whether your investment genuinely enhances your lifestyle or becomes expensive disappointment.
Standard Conservatory Reality
Summer: Too hot June through August unless you install expensive cooling or live with closed blinds defeating the purpose
Winter: Too cold November through February despite significant heating costs
Spring/Autumn: Generally pleasant but temperature still requires management
Practical result: You use it comfortably about 6-7 months per year. The other 5-6 months it’s either uncomfortably hot or prohibitively expensive to heat adequately.
The Hidden Cost
£20,000 investment divided by 50% usability = £40,000 per genuinely usable space.
Advanced Glazing Reality
Structures with New Generation Glass or equivalent temperature-control glazing provide unmatched comfort and usability all year round.
Summer: Comfortable even during heatwaves because solar heat gain is actively managed, not just insulated against
Winter: Comfortable with reasonable heating because excellent insulation and passive solar heat gain (when welcome) reduce heating requirements dramatically
Practical result: Genuine daily use throughout the year. Not a seasonal space requiring temperature management but true living space you instinctively use like any other room.
The Lifestyle Impact
When conservatory becomes genuinely usable year-round, it transforms how you inhabit your property. Morning coffee space regardless of season. Home office that actually works in August and January. Dining area you can rely on. Reading room you gravitate toward naturally.
This isn’t marginal benefit. It’s the difference between spending £50,000 on a space you love and use daily versus spending £25,000 on a space you tolerate seasonally.
The Multi-Generational Durability Question Nobody Asks
Here’s the conversation almost never happening in conservatory showrooms: how long will this actually last?
Sales focus on guarantees (10 years, 15 years) creating impression these timeframes matter. They don’t, really.
What Actually Matters
Will your conservatory still be beautiful and functional in 30 years? 50 years?
Standard Conservatory Over 50 Years
Initial installation cost
Plus complete replacement at 20-25 years
Plus ongoing maintenance
= Two complete conservatories worth of investment
Bespoke Conservatory Over 50 Years
Single installation investment
Regular professional maintenance
= One conservatory worth of investment
Plus vastly superior experience throughout
Over realistic property ownership periods, genuine quality costs similar to repeatedly replacing cheaper options whilst providing vastly superior experience throughout.
The Sustainability Question
Replacing entire structures after 20-25 years generates massive material waste and carbon impact. Structures designed for 50+ year lifespans align with genuine sustainability principles.
Begin Your Bespoke Conservatory Journey
Your conservatory will either enhance your property architecturally and provide genuinely year-round comfortable space for generations, or it’ll be a structure you tolerate for a decade before facing expensive problems.
The designer you select determines which outcome you achieve.
What to Prioritise
Established expertise over marketing: Companies with 50+ years designing and building bespoke glass extensions have proven capability through sustained excellence, not advertising claims
Advanced glazing technology over standard glass: Temperature-control glazing like New Generation Glass fundamentally differs from standard double glazing, enabling genuine year-round comfort versus seasonal use
Individual architectural design over style selection: Bespoke means designed specifically for your property and lifestyle, not choosing from predetermined templates
Premium materials over mass-produced: Hardwood timber or high-specification aluminium provide multi-generational durability impossible with standard materials
Comprehensive service over component supply: Professional project management from design through completion versus coordinating multiple contractors yourself
The Investment Difference
The investment difference between standard conservatories and genuinely bespoke design reflects fundamental quality distinctions: architectural design versus product selection, advanced technology versus standard glazing, 50+ year lifespan versus 20-25 year expectancy.
For properties where architectural quality matters and spaces you’ll genuinely treasure for decades, bespoke design represents appropriate investment. The question isn’t cost but value over the genuine lifespan and whether anything less will truly satisfy.
Begin by identifying specialists demonstrating proven capability through operational longevity, technology innovation, professional recognition, and comprehensive service delivery. Your conservatory journey starts with the right designer. Choose wisely.
FAQ: Bespoke Conservatories, Orangeries and Glass Extensions
What is a truly bespoke conservatory?
A truly bespoke conservatory is individually designed for your specific property and lifestyle, not chosen from a standard range. It combines architectural design, advanced temperature-control New Generation Glass, and premium materials such as hardwood or aluminium to create a room you can use comfortably all year.
How long should a high-quality bespoke conservatory last?
With premium materials such as hardwood or high-specification aluminium, and correct maintenance, a bespoke conservatory or orangery can be designed for a 50-year plus lifespan. Standard uPVC systems typically need major replacement after 20–25 years.
Why is New Generation Glass better than standard “energy-efficient” glass?
Standard double glazing mainly insulates. New Generation Glass uses advanced coatings to actively manage solar heat gain – keeping spaces cooler in summer and warmer in winter, so your conservatory feels like a proper room instead of a space you can only tolerate in certain seasons.
Do bespoke conservatories meet UK Building Regulations?
Conservatories are normally classed as thermally separated structures with doors between the house and the conservatory. Fully open glass extensions, however, must comply with full extension standards. A genuine specialist will design and specify the right solution and handle Building Regulations on your behalf.
What’s the difference between an orangery, a conservatory and a glass extension?
An orangery is a more solid, room-like structure with brick or stone pillars and a solid roof with a central lantern. A conservatory is usually more than 75% glass in the roof and walls, with a lighter, more transparent feel. A glass extension is a fully integrated building extension that moves the home’s thermal envelope, meeting much higher insulation standards than a traditional conservatory.
Where does Room Outside work?
Room Outside designs and builds luxury bespoke conservatories, orangeries and glass extensions from its base in West Sussex, covering the South East of England, including Surrey, Hampshire, Sussex, Kent, Essex, Dorset, Berkshire and Greater London.
Ready to Create Your Bespoke Conservatory?
Work with established conservatory specialists with over 50 years of experience designing and building luxury bespoke conservatories, orangeries and glass extensions across the South East of England.
Bespoke Conservatory Design: Creating Spaces That Transform How You Live
Learn what genuine bespoke design means, why New Generation Glass creates conservatories you’ll love year-round, and how to find true specialists who protect your investment.
25 min read
South East England
50+ Years Expertise
Quick Answer
True bespoke conservatory design means creating an architectural masterpiece engineered specifically for your property using premium materials like hardwood or aluminium, advanced temperature-control glazing such as New Generation Glass, and individual design that respects your home’s character. The difference between bespoke design and standard conservatories isn’t just quality; it’s the difference between a space you’ll treasure for generations and one you’ll tolerate for a decade.
For over 50 years, Room Outside, based in West Sussex, has been designing and building luxury bespoke conservatories, orangeries and glass extensions across the South East of England, including Surrey, Hampshire, Sussex, Kent and Greater London. That experience means we know exactly what works for UK homes and UK weather.
Stand in any beautifully designed conservatory on a crisp January morning, sunlight streaming through perfectly engineered glass, warmth enveloping you despite the frost outside. This isn’t luck. It’s not even expensive heating. It’s what happens when genuine architectural expertise meets advanced glazing technology.
Yet most UK homeowners will never experience this. They’ll settle for spaces that feel like greenhouses in July and ice boxes in December, wondering why their £20,000 investment only gets used six months of the year.
The difference? Understanding what “bespoke” actually means, and why it matters far more than most conservatory companies will ever admit.
Why Most “Bespoke” Conservatories Aren’t Actually Bespoke At All
Walk into most conservatory showrooms and you’ll hear the word “bespoke” within the first five minutes. They’ll show you Victorian styles, Edwardian options, perhaps a contemporary lean-to. You’ll pick your size from a measuring tape, your colour from a chart, maybe some decorative glazing bars from a catalogue.
They’ll call this “bespoke.”
It isn’t.
What’s really happening: You’re selecting from pre-engineered modular systems, choosing options like ordering from a menu. Made-to-measure? Yes. Custom colours and features? Certainly. But individually designed for your specific property’s architecture, orientation, and your lifestyle? Not remotely.
The Suit Analogy
Think of it like buying a suit. Most high street shops offer “made-to-measure” services. They’ll adjust standard patterns for your measurements, perhaps offer fabric choices. That’s what most conservatory companies provide.
True bespoke is what happens when a master tailor studies your build, your posture, how you move, what you’ll wear it for, and creates something that exists nowhere else in the world. Every seam, every dart, every detail considered specifically for you.
That’s the difference we’re talking about with conservatory design.
The Three Critical Elements That Define Genuine Bespoke Design
Room Outside brings over 50 years of expertise to the art of designing and building bespoke glass extensions, creating structures that blend timeless elegance with innovative functionality.
Real bespoke design begins with architectural analysis. The designer studies your property like an art historian examining a painting. What period is it? What are the proportions telling us? How do the roof lines interact? What’s the rhythm of the windows? What materials create the character?
Then they look at you. How do you live? When do you use spaces? Do you entertain? Work from home? Have small children or grandchildren visiting? Love gardening? Read for hours? Cook elaborate meals?
Only then does design begin. Not selecting from templates, but creating something unique that:
Respects your property’s architectural DNA
Enhances rather than compromises its character
Works specifically for your lifestyle patterns
Responds to your site’s unique orientation and microclimate
Creates proportions and rhythms that feel inevitable, as if it was always meant to be there
The tell-tale sign you’re not getting bespoke design: The conversation focuses on style selection (“Victorian or Edwardian?”) rather than architectural analysis of your specific property.
2. Advanced Glazing Technology (Not Just “Energy-Efficient” Glass)
Here’s where most conservatory companies lose the plot entirely. They’ll talk about “energy-efficient glass” or “solar control glazing” as if it’s all basically the same thing with minor variations.
It categorically isn’t.
Standard double glazing insulates. That’s useful, but it doesn’t solve the fundamental problem: glass conducts temperature. Traditional conservatories experience wild temperature swings because the glass transmits solar heat in summer and radiates heat out in winter.
Room Outside pioneered the introduction of New Generation Glass from the USA over 20 years ago, further developing it to suit the British climate, enabling structures that provide unmatched comfort and usability all year round.
Advanced temperature-control glazing like New Generation Glass does something entirely different. It actively manages solar radiation, selectively filtering wavelengths that create heat whilst maintaining visible light transmission. It’s not just thicker or better insulated; it’s fundamentally different technology.
What This Means in Practice
Summer afternoon, blazing sunshine: your neighbour’s conservatory reads 38°C and is unusable. Yours? A comfortable 23°C. No air conditioning. No giant fans. Just intelligent glazing working exactly as engineered.
January evening, frost forming outside: you’re sitting in your conservatory reading without a jumper because the combination of advanced glazing and modest heating creates comfortable, stable temperatures that traditional conservatories simply cannot achieve regardless of how much you spend heating them.
15-25°C
Temperature variation with standard conservatory
5-8°C
Temperature variation with advanced glazing
20+ yrs
UK development of New Generation Glass
That’s not marginal improvement. That’s the difference between a space you occasionally tolerate and one you genuinely live in daily.
The tell-tale sign you’re not getting advanced glazing: They talk about glass thickness and insulation but can’t explain how solar heat gain is actively managed or provide specific performance data for your orientation.
Premium aluminium: Custom extrusions, ultra-fine sightlines (as low as 20mm), exceptional strength for larger glass spans
Visual Character
uPVC: Always looks like uPVC, regardless of colour or woodgrain effects
Hardwood: Warmth, depth, grain character that improves with age
Premium aluminium: Clean, precise, contemporary aesthetic impossible with other materials
For properties where architectural integrity matters, material selection isn’t about budget. It’s about whether the conservatory enhances or compromises your property’s character for the next half-century.
The tell-tale sign you’re not getting premium materials: The conversation focuses primarily on uPVC with hardwood positioned as an expensive upgrade rather than the appropriate choice for your property’s architectural quality.
What’s the Difference Between an Orangery, a Conservatory and a Glass Extension?
Quick Answer
An orangery is a more solid, room-like structure with brick or stone pillars and a solid roof with a central lantern. A conservatory is usually more than 75% glass in the roof and walls, with a lighter, more transparent feel. A glass extension is a fully integrated building extension that moves the home’s thermal envelope, meeting much higher insulation standards than a traditional conservatory.
What Makes an Orangery Different (And Why It Matters)
Orangeries have a solid roof with less than 75% glazing and feature substantial masonry construction with brick or stone pillars, creating more solid structure than conservatories which typically have over 75% roof glazing.
Think of orangeries as proper rooms with exceptional natural light rather than glass structures with some solid elements.
The solid roof perimeter creates an internal plastered pelmet running around the room’s edge. This provides:
Space for downlighting creating proper room ambiance (impossible with all-glass roofs)
Visual weight and enclosure making it feel like a room, not a greenhouse
Superior thermal performance through insulation mass
Architectural presence that brick or stone pillars reinforce
Walk into a well-designed orangery and you don’t think “conservatory.” You think “beautiful room with extraordinary light.”
When Orangeries Make Sense
You want proper room character, not indoor-outdoor transitional space
Year-round thermal comfort is non-negotiable
Your property’s architecture has sufficient presence
Extending kitchen or dining space where room character matters
Privacy from neighbours or overlooking is important
When Conservatories Work Better
Maximum connection to garden is priority
You love the light, transparent character of glass structures
Your property’s style suits lighter architectural language
You want that magical indoor-outdoor blurred boundary
Budget favours predominantly-glazed structures
Neither is inherently “better.” They’re different architectural responses to different requirements and properties.
Glass Extensions: The Contemporary Alternative That Changes Everything
A glass extension is a true building extension that’s fully open to the existing house. It moves the external thermal envelope, so it has to meet much higher insulation standards than a thermally separated glass conservatory with doors between the house and the structure.
The critical distinction: Building Regulations classify conservatories as thermally-separated structures (doors between conservatory and house). Glass extensions are fully-integrated, meaning they must meet full extension thermal performance standards.
What This Enables
Glass extensions can incorporate advanced technologies that conservatories often don’t:
Triple glazing as standard (U-values as low as 0.5 W/m²K)
Heated glass technology
Full integration with home heating systems
Contemporary architectural language
The Structural Glass Revolution
Contemporary frameless glass extensions use structural glass technology completely different from traditional conservatories. Laminated glass beams and fins create self-supporting structures with minimal visible framework. We’re talking 20-40mm ultra-fine profiles versus 100-150mm traditional conservatory frames.
Visual impact? Completely different. Where traditional conservatories have substantial framework creating that recognisable “conservatory” aesthetic, structural glass extensions achieve near-frameless transparency.
Why Premium Bespoke Orangeries Outperform Kit-Built Systems
The orangery market has exploded over the past decade. Unfortunately, so has confusion about what constitutes quality orangery design.
Most “orangery systems” offered by conservatory companies are pre-engineered modular kits with standard column spacing, predetermined lantern sizes, and generic architectural detailing. You’re selecting configurations, not commissioning design.
What Genuine Bespoke Orangery Design Delivers Differently
Architectural Integration
The designer studies your property’s existing architecture. If it’s Victorian, what are the typical Victorian orangery proportions? What column spacing and heights create appropriate rhythm? What cornice profiles and architectural details complement your existing mouldings?
If contemporary, how do we create an orangery interpretation that feels current rather than pastiche? What materials bridge traditional orangery form with modern architectural language?
This level of analysis simply doesn’t happen with kit systems.
Structural Sophistication
The insulated roof structure, column dimensions, load distribution, and foundation engineering are all designed specifically for your project’s requirements and soil conditions.
Kit systems use standardised engineering applied broadly. Usually adequate, but not optimised for your specific context.
Material Quality
True bespoke specialists offer luxury hardwood timber, aluminium, and masonry materials selected and specified specifically for each project, not predetermined system components.
The brickwork matches your property’s existing brick. The timber species, profiles, and finishes are selected for your architectural context. The lantern design is proportioned specifically for your orangery’s dimensions.
The Investment Perspective
Yes, genuinely bespoke orangery design requires substantially more investment than kit systems. But we’re talking about structures designed to enhance your property for 50+ years, not 20.
The question isn’t cost; it’s value over the genuine lifespan.
How Frameless Glass Extensions Differ From Everything Else
If you’ve only seen traditional conservatories, encountering a frameless glass extension is revelatory.
The fundamental difference: Instead of glass panels held in metal frames, structural glass units support themselves using laminated glass beams, glass fins, and structural silicone bonding. The glass is the structure.
This enables architectural possibilities impossible with conventional framing:
Corner glazing without vertical posts (uninterrupted 90-degree glass corners)
Cantilever sections
Asymmetric geometries
Continuous glass runs uninterrupted by visible framework
Walk into a frameless glass extension and the sensation is completely different from traditional conservatories. The transparency is extraordinary. Sightlines remain unbroken. Connection to landscape becomes immersive rather than merely visual.
When Frameless Glass Extensions Excel
Contemporary architectural aesthetic speaks to you
Maximum transparency is priority
Your property or project suits cutting-edge design
Garden or landscape has exceptional visual appeal
You want something architecturally distinctive
When Traditional Framing Works Better
Period property where contemporary materials feel inappropriate
Budget favours conventional construction
You prefer warmer visual character of timber frameworks
Traditional architectural language suits your property better
Neither approach is superior. They’re different architectural responses to different contexts and preferences.
The New Generation Glass Difference: Why 20 Years of UK Development Matters
Room Outside was the first company in England to introduce New Generation Glass from the USA over 20 years ago and further developed it to suit the British climate.
Let’s talk about what that actually means and why it matters for anyone considering a serious conservatory investment.
Standard “energy-efficient” glazing insulates. Multiple glass layers with gas-filled cavities reduce heat transfer. That’s useful, particularly for windows in solid walls.
But conservatories are predominantly glass. Insulation alone doesn’t solve the fundamental challenge: managing solar heat gain whilst maintaining transparency and insulation performance.
What Temperature-Control Glazing Does Differently
Sophisticated coatings applied to glass surfaces selectively filter solar radiation. Infrared wavelengths that create heat are reflected or absorbed, whilst visible light passes through relatively unimpeded.
The result: A conservatory roof can receive full summer sun without the interior becoming unbearably hot, because the heat component of sunlight is being filtered before it enters the space.
Why UK Climate Development Matters
USA and UK have fundamentally different climate challenges:
USA (particularly southern states): Extreme summer heat, solar gain management paramount
UK: Moderate summers but significant heating season, balance between solar control and heat retention crucial
Room Outside’s development of New Generation Glass for British climate means optimising this balance specifically for UK conditions:
Summer: Sufficient solar control to prevent overheating
Winter: Optimal light transmission and insulation to minimise heating requirements
Spring/Autumn: Passive solar heat gain that’s welcome, but controlled so the room doesn’t overheat
This climate-specific optimisation is why 20+ years of UK development matters. It’s not just licensing American technology; it’s adapting and refining it for genuinely different climate requirements.
How You Experience This
Your conservatory becomes a space you instinctively use year-round without thinking about temperature. No longer “should I turn the heating up?” or “it’s too hot in here.” Just comfortable space that works throughout the seasons.
That unconscious usability is the point. The best design becomes invisible; you simply live in beautiful, comfortable space without constantly managing its shortcomings.
What Truly Sets Bespoke Specialists Apart From Standard Conservatory Companies
After 50+ years in this industry, certain patterns become crystal clear about what distinguishes genuine specialists from companies offering standard products with “bespoke options.”
Operational Longevity Proves Sustained Excellence
Room Outside has spanned over 5 decades in business, offering expert experience designing and building bespoke glass extensions throughout the South East of England and further afield.
Half a century is a long time in any industry. Companies don’t achieve that longevity through marketing. They achieve it through:
Consistently delivering quality that generates referrals
Adapting to changing technologies whilst maintaining craft excellence
Building reputations that architects and construction professionals trust
Creating structures that still delight homeowners decades later
Why This Matters for You
When you invest in genuine bespoke design, you’re not just buying a structure. You’re starting a relationship with a company you’ll potentially work with again (repairs, maintenance, future projects) over decades.
Established specialists will still be there in 15 years when you want that roof panel replaced. They’ll still have craftspeople who understand their structures. Their reputation still depends on your satisfaction.
New entrants? Who knows.
Technology Leadership Versus Technology Following
Being the first company in England to introduce New Generation Glass over 20 years ago demonstrates genuine innovation leadership rather than following market trends.
Most conservatory companies adopt technologies once they’re mainstream and proven. Nothing wrong with that for standard products, but it reveals their market position.
True specialists invest in emerging technologies years before mainstream adoption. They develop relationships with innovative manufacturers globally. They’re willing to be pioneers because they’re genuinely focused on technical excellence, not just selling products.
Professional Specification Recognition
Award-winning Room Outside products have been specified for some of the most iconic buildings in the UK, earning an enviable reputation among the UK’s leading architectural practices and construction companies.
Architects and construction professionals don’t specify conservatory suppliers based on consumer advertising. They specify based on:
Technical competence and reliability
Quality consistency
Ability to deliver complex projects successfully
Responsiveness to design requirements
Problem-solving capability when challenges arise
Professional specification is the strongest indicator of genuine technical credibility.
Listed Building and Conservation Expertise
Specialists demonstrate capability across luxury hardwood timber, aluminium, and frameless glass extensions for grade one and grade two listed buildings and properties in National Parks and areas of outstanding natural beauty.
Securing Listed Building consent or planning approval in conservation areas requires:
Deep understanding of architectural heritage
Ability to design additions that conservation officers accept
Respect for historical architecture without pastiche
This expertise proves a level of architectural sophistication that standard conservatory companies rarely possess.
Even if your property isn’t listed: Companies with listed building expertise bring that same architectural sensitivity to all projects. They understand proportion, detail, materials, and integration in ways that benefit any property where quality matters.
Finding True Bespoke Conservatory Specialists: What to Look For
Most conservatory shopping focuses on wrong indicators. People compare prices across similar-seeming quotes, not realising they’re comparing fundamentally different quality levels.
The Design Consultation Reveals Everything
Quality designers work closely with clients from start to finish, exploring ideas and taking inspiration from the architecture of your home and your lifestyle.
In your first meeting, are they:
Studying your property’s architecture in detail?
Walking around examining roof lines, proportions, materials, existing architectural features?
Asking extensive questions about how you live, what matters to you, your long-term plans?
Or are they quickly measuring up and pulling out standard design catalogues?
The quality of that initial consultation tells you everything about whether you’re talking to a designer or a salesperson.
Portfolio Quality Over Portfolio Size
Don’t just count completed projects. Look at them critically:
Do the conservatories look architecturally integrated with their properties? Each should feel like it belongs, not like it was added. If everything looks similar regardless of property type, that’s a red flag.
Is there genuine design variety? You should see different architectural responses to different contexts. Similar-looking projects across different properties reveal predetermined solutions, not bespoke design.
Are there challenging projects? Listed buildings? Awkward sites? Unique architectural contexts? Complex requirements? These reveal problem-solving capability.
Technology Specificity Versus Generic Claims
“We use energy-efficient glass” means nothing. Every conservatory company says that.
What reveals genuine technology expertise:
Can they explain specific glazing specifications for your project?
Discuss U-values, solar heat gain coefficients, light transmission ratios?
Explain why they’d recommend particular glazing for your orientation and microclimate?
Articulate advanced systems like New Generation Glass and explain specifically how temperature-control glazing differs from standard insulation?
Generic descriptions like “keeps you cooler in summer and warmer in winter” are sales-speak. Technical specificity reveals genuine understanding.
Material Options Indicate Company Focus
If the conversation defaults to uPVC with hardwood positioned as expensive premium upgrade, that tells you where their focus lies.
Quality specialists discuss materials as architectural choices appropriate for different contexts, not budget tiers.
For many properties, hardwood is simply the right material regardless of cost. For contemporary projects, premium aluminium might be optimal. The conversation should be about what’s appropriate for your property and project, not what’s cheapest or most profitable.
Project Management Approach
True specialists take responsibility for planning and installation, providing complete peace of mind with comprehensive project management.
Who’s managing:
Planning applications if needed?
Building Regulations approval?
Foundation contractor coordination?
Construction timeline?
Problem resolution?
Final commissioning?
With quality specialists: They manage everything. Single point of accountability.
With component suppliers: You coordinate multiple contractors yourself.
The difference matters enormously for stress levels and ultimate quality.
The Questions That Reveal Everything
Want to know instantly whether you’re talking to genuine specialists? Ask these questions and pay attention to how they answer.
Ask These Before Committing
1. “How do you approach designing for properties like mine?”
Quality answer: Discusses architectural analysis, understanding your specific property’s character, how they develop individual design responses.
Red flag answer: Talks about selecting from their range of styles.
2. “What proportion of your projects are genuinely bespoke versus standard designs adapted by size?”
Quality answer: Honest about their focus. True specialists will say 80-100% genuinely individual design.
Red flag answer: Vague about the distinction or defensive about the question.
3. “What glazing would you specify for my project and why?”
Quality answer: Discusses specific technologies, your orientation, microclimate factors, performance expectations with technical specificity. Should mention advanced options like New Generation Glass.
Red flag answer: Generic “energy-efficient glass” without technical details.
4. “How long have you been designing and building bespoke conservatories specifically?”
Quality answer: 25+ years ideally, with consistent focus on quality glass extensions.
Red flag answer: Recent entrant or conservatories as recent addition to general building/windows business.
5. “Can you show me projects on listed buildings or in conservation areas?”
Red flag answer: Limited or no listed building experience.
6. “Who would design my conservatory and how does that process work?”
Quality answer: Named designer with architectural background, describes collaborative design development process.
Red flag answer: Vague about designer identity or process jumps from initial meeting to quotation without design development.
7. “Can you provide customer references for similar projects?”
Quality answer: Readily provides multiple contacts with similar property types and project scales.
Red flag answer: Reluctant to provide references or only offers vastly different project types.
Their comfort answering these questions tells you whether they’re confident in their expertise or hoping you won’t dig too deep.
Modern Design Ideas That Show What’s Possible in 2025
Let’s get specific about what exceptional bespoke design can achieve for different property types and lifestyle requirements.
Contemporary Side-Return Extensions for Urban Living
Victorian and Edwardian terraced houses throughout UK cities have narrow side-return spaces that traditionally house bins and bikes. Barely functional, often eyesores.
Clever glass extension design transforms these spaces into light-filled kitchen or living extensions that revolutionise how you use your ground floor.
Design approach: Full-height glazing on side elevation and rear, maximising light in inherently narrow, shaded positions. Flat glass roof carefully detailed to meet party wall and boundary constraints. Integration with large-span sliding doors opening to garden.
The challenge: Achieving comfortable thermal performance in highly-glazed urban positions where neighbouring properties limit ventilation.
Solution: Advanced solar control glazing preventing overheating, sophisticated artificial lighting design for evening use, careful ventilation strategy using automated rooflights.
Result: Previously wasted space becomes your favourite room. Natural light floods into previously dark side-return corridors. Kitchen expands into bright, usable space. Property value increases dramatically.
Structural Glass Boxes for Contemporary Properties
If your property’s architecture is contemporary or you’re adding contemporary extension to traditional home, frameless structural glass offers architectural possibilities unachievable with traditional conservatories.
Design concept: Glass beams and fins creating self-supporting structure with minimal visible framework. Corner glazing without vertical posts creates uninterrupted 90-degree glass corners. Ultra-fine profiles (20-30mm) appearing almost invisible.
Walk inside and the effect is extraordinary. Traditional conservatories, even nice ones, have framework interrupting sightlines. Structural glass extensions achieve near-transparency. It feels like inhabiting outdoor space whilst being comfortably protected.
Contemporary Orangeries with Clean Architectural Lines
Traditional Victorian or Georgian orangery styling feels wrong on many properties. But the orangery form itself—solid perimeter roof with central glazed lantern, brick or stone elements—remains architecturally excellent.
Modern interpretation: Clean-lined brick or rendered pillars without decorative mouldings. Flat super-insulated roof with contemporary aluminium lantern featuring minimal profiles. Floor-to-ceiling glazing between solid elements. Internal plastered pelmet providing downlighting locations.
Result: Orangery thermal comfort and room character without pastiche period styling. Works beautifully on contemporary properties or as clearly-contemporary addition to traditional homes. The visual language says “this is now” whilst respecting orangery architectural principles developed over centuries.
Garden Room Conservatories with Horizontal Emphasis
Traditional pitched-roof conservatory forms don’t suit every property or preference. Low-pitch or flat glass roofs create dramatically different aesthetic.
Design approach: Wide, low proportions emphasising horizontal lines rather than vertical pitch. Glass roof at 5-15 degrees or completely flat with concealed edge detailing. Large-span doors (4-6 metres) opening entire wall to garden.
Critical requirement: Excellent solar control glazing preventing overheating in low-pitch configurations. Standard glass in shallow-pitch roofs creates furnace conditions in summer.
Result: Contemporary garden room aesthetic distinct from traditional conservatory forms. Particularly appropriate for bungalows or single-storey extensions where restricted height requires low-pitch solutions.
Timber-Framed Extensions with Exposed Structure
For properties where natural materials and craft aesthetic matter, exposed hardwood timber structural framework creates warmth impossible with aluminium or uPVC.
Design concept: Substantial timber posts and beams (150-200mm sections) creating visible architectural structure. Timber rafters expressed internally rather than hidden. Large glass panels between timber framework. Natural timber finishes or contemporary painted colours.
Result: Architectural character and material warmth distinct from both ultra-minimal glass boxes and traditional conservatories. Particularly appropriate for rural properties, period homes where quality materials matter, or anyone who simply loves natural materials and visible craftsmanship.
Why Year-Round Comfort Matters More Than You Might Think
Here’s something most people don’t consider until it’s too late: conservatory usability determines whether your investment genuinely enhances your lifestyle or becomes expensive disappointment.
Standard Conservatory Reality
Summer: Too hot June through August unless you install expensive cooling or live with closed blinds defeating the purpose
Winter: Too cold November through February despite significant heating costs
Spring/Autumn: Generally pleasant but temperature still requires management
Practical result: You use it comfortably about 6-7 months per year. The other 5-6 months it’s either uncomfortably hot or prohibitively expensive to heat adequately.
The Hidden Cost
£20,000 investment divided by 50% usability = £40,000 per genuinely usable space.
Advanced Glazing Reality
Structures with New Generation Glass or equivalent temperature-control glazing provide unmatched comfort and usability all year round.
Summer: Comfortable even during heatwaves because solar heat gain is actively managed, not just insulated against
Winter: Comfortable with reasonable heating because excellent insulation and passive solar heat gain (when welcome) reduce heating requirements dramatically
Practical result: Genuine daily use throughout the year. Not a seasonal space requiring temperature management but true living space you instinctively use like any other room.
The Lifestyle Impact
When conservatory becomes genuinely usable year-round, it transforms how you inhabit your property. Morning coffee space regardless of season. Home office that actually works in August and January. Dining area you can rely on. Reading room you gravitate toward naturally.
This isn’t marginal benefit. It’s the difference between spending £50,000 on a space you love and use daily versus spending £25,000 on a space you tolerate seasonally.
The Multi-Generational Durability Question Nobody Asks
Here’s the conversation almost never happening in conservatory showrooms: how long will this actually last?
Sales focus on guarantees (10 years, 15 years) creating impression these timeframes matter. They don’t, really.
What Actually Matters
Will your conservatory still be beautiful and functional in 30 years? 50 years?
Standard Conservatory Over 50 Years
Initial installation cost
Plus complete replacement at 20-25 years
Plus ongoing maintenance
= Two complete conservatories worth of investment
Bespoke Conservatory Over 50 Years
Single installation investment
Regular professional maintenance
= One conservatory worth of investment
Plus vastly superior experience throughout
Over realistic property ownership periods, genuine quality costs similar to repeatedly replacing cheaper options whilst providing vastly superior experience throughout.
The Sustainability Question
Replacing entire structures after 20-25 years generates massive material waste and carbon impact. Structures designed for 50+ year lifespans align with genuine sustainability principles.
Begin Your Bespoke Conservatory Journey
Your conservatory will either enhance your property architecturally and provide genuinely year-round comfortable space for generations, or it’ll be a structure you tolerate for a decade before facing expensive problems.
The designer you select determines which outcome you achieve.
What to Prioritise
Established expertise over marketing: Companies with 50+ years designing and building bespoke glass extensions have proven capability through sustained excellence, not advertising claims
Advanced glazing technology over standard glass: Temperature-control glazing like New Generation Glass fundamentally differs from standard double glazing, enabling genuine year-round comfort versus seasonal use
Individual architectural design over style selection: Bespoke means designed specifically for your property and lifestyle, not choosing from predetermined templates
Premium materials over mass-produced: Hardwood timber or high-specification aluminium provide multi-generational durability impossible with standard materials
Comprehensive service over component supply: Professional project management from design through completion versus coordinating multiple contractors yourself
The Investment Difference
The investment difference between standard conservatories and genuinely bespoke design reflects fundamental quality distinctions: architectural design versus product selection, advanced technology versus standard glazing, 50+ year lifespan versus 20-25 year expectancy.
For properties where architectural quality matters and spaces you’ll genuinely treasure for decades, bespoke design represents appropriate investment. The question isn’t cost but value over the genuine lifespan and whether anything less will truly satisfy.
Begin by identifying specialists demonstrating proven capability through operational longevity, technology innovation, professional recognition, and comprehensive service delivery. Your conservatory journey starts with the right designer. Choose wisely.
FAQ: Bespoke Conservatories, Orangeries and Glass Extensions
What is a truly bespoke conservatory?
A truly bespoke conservatory is individually designed for your specific property and lifestyle, not chosen from a standard range. It combines architectural design, advanced temperature-control New Generation Glass, and premium materials such as hardwood or aluminium to create a room you can use comfortably all year.
How long should a high-quality bespoke conservatory last?
With premium materials such as hardwood or high-specification aluminium, and correct maintenance, a bespoke conservatory or orangery can be designed for a 50-year plus lifespan. Standard uPVC systems typically need major replacement after 20–25 years.
Why is New Generation Glass better than standard “energy-efficient” glass?
Standard double glazing mainly insulates. New Generation Glass uses advanced coatings to actively manage solar heat gain – keeping spaces cooler in summer and warmer in winter, so your conservatory feels like a proper room instead of a space you can only tolerate in certain seasons.
Do bespoke conservatories meet UK Building Regulations?
Conservatories are normally classed as thermally separated structures with doors between the house and the conservatory. Fully open glass extensions, however, must comply with full extension standards. A genuine specialist will design and specify the right solution and handle Building Regulations on your behalf.
What’s the difference between an orangery, a conservatory and a glass extension?
An orangery is a more solid, room-like structure with brick or stone pillars and a solid roof with a central lantern. A conservatory is usually more than 75% glass in the roof and walls, with a lighter, more transparent feel. A glass extension is a fully integrated building extension that moves the home’s thermal envelope, meeting much higher insulation standards than a traditional conservatory.
Where does Room Outside work?
Room Outside designs and builds luxury bespoke conservatories, orangeries and glass extensions from its base in West Sussex, covering the South East of England, including Surrey, Hampshire, Sussex, Kent, Essex, Dorset, Berkshire and Greater London.
Ready to Create Your Bespoke Conservatory?
Work with established conservatory specialists with over 50 years of experience designing and building luxury bespoke conservatories, orangeries and glass extensions across the South East of England.
A Basic Guide to Frameless Glass & Glass Box Extensions
Frameless glass and frameless glass box extensions have become very popular choices. This guide will help you understand the basics.
Structural glass is a highly sought-after design material used to create contemporary structures. It is commonly used to enclose balconies and staircases, open solid walls to the outdoors, and even serve as feature flooring. The sleek lines and minimalist appeal of frameless glass help homeowners achieve a modern, high-end aesthetic with a true wow-factor finish.
Design Versatility
One of the greatest advantages of frameless glass is its versatility. It can be used for various applications, including:
Large, all-glass extensions.
Side return extensions.
Roof lights to increase natural light.
The clean, non-intrusive aesthetic of frameless glass means it blends seamlessly with existing architecture. Surprisingly, it is a popular choice for older and listed properties as it adds style without overshadowing the original building. Frameless glass and frameless box extensions can be designed in numerous shapes, including lean-to, gable-ended, hexagonal, or a simple box structure.
Do You Need anArchitect?
You may wonder whether hiring an architect is necessary for your glass extension project. The answer depends on the complexity of your design.
For straightforward projects, a specialist glass installation company can draft the required plans.
For complex structures requiring planning permission, an architect may be beneficial to ensure compliance and a seamless integration with your home.
Planning Permission
In most cases, frameless glass extensions fall under permitted development rules, meaning that they do not require planning permission. However, there are exceptions:
If your home is listed or located in a conservation area, planning permission is necessary.
If your property has already been extended, it may exceed permitted development limits.
It is always advisable to check with your local planning authority before beginning any construction.
Energy EfficiencyMatters
Frameless glass extensions offer exceptional energy efficiency when built using high-performance glass. Features include:
Low-emissivity (Low-E) coatings that reduce heat loss.
UV filtering to minimise glare and prevent furniture fading.
Argon gas-filled glazing for superior insulation.
Because frameless structures incorporate more glass than traditional framed extensions, investing in high-specification temperature-controlled glass is crucial. Superior glazing ensures comfort throughout the year and meets the latest regulations regarding overheating in homes due to climate change.
Durabilityand Strength
The structural glass used in frameless extensions is incredibly strong. Designed to withstand the elements, it meets Class A of BS6206 building regulations for safety and durability.
Key durability features:
Toughened or laminated glass for added strength.
Roof glass that is robust enough to be walked on.
Minimal maintenance requirements for long-term performance.
Creative Ways to Use Frameless Glass
Glass Rooms
Glass rooms make a bold design statement, seamlessly blending indoor and outdoor spaces. They allow natural light to flood in, removing barriers between your home and garden. Installing bi-fold or double doors enhances this connection, creating an effortless transition for entertaining and relaxation.
These rooms are incredibly versatile and can serve various functions. They provide a tranquil retreat, a stylish dining area, or even a creative workspace. Many homeowners also use glass extensions as multipurpose rooms, combining kitchen, dining, and living areas into a single, open-plan layout. This flexibility makes them an excellent choice for modern living.
Glass Wall
Replacing an external wall with frameless glass can dramatically transform a space, making it feel larger and brighter without physically extending the footprint of your home.
Balustrades
For a stylish and practical interior upgrade, glass balustrades can enhance staircases and landings. They allow more light into darker areas, creating a sense of openness.
Glass Floor
Structural glass flooring is ideal for:
Roof terraces.
Bringing light into lower levels, such as basement rooms or entrance halls.
Roof Lights
Adding frameless glass roof lights enhances areas like kitchen extensions, bringing in additional daylight while maintaining privacy. Apex-style roof lights can create a striking focal point.
Glass Doors
Complete your glass extension with sleek door options, including:
Frameless French doors that fold back for a seamless transition.
Fine-framed sliding doors for a modern finish.
Bi-fold doors to create an uninterrupted indoor-outdoor flow.
Start Your Frameless Glass Project
Are you ready to create a breathtaking frameless glass extension? Our experts are here to help you explore design options, understand costs, and bring your vision to life.
Check out our gallery for inspiration and contact us today to start planning your bespoke frameless glass project.
When you think of an orangery, conservatory or glass box extensions, you most likely envision a medium to large structure. But, a glass structure doesn’t have to be huge to add value to you and your home. Sometimes even the smallest of glass extensions can make the biggest of impacts. Adding a frameless glass side return to extend the kitchen out to the property boundary, a glass box structure to cover a staircase where it opens to the roof garden, replacing a solid roof with structural glass or creating a wooden framed orangery entranceway can make a big difference to the aesthetics as well as practicalities of day to day life. If you don’t have the space to add a larger orangery or conservatory, perhaps thinking about a smaller but perfectly planned and designed structure could make all the difference to your lifestyle.
Get Some Inspiration for a Small but Perfectly Formed Glass Extension
Here are some great examples of how small glass structures can enhance your home even when you don’t have the space, or budget or even if you don’t want to add a huge structure:
Round Frameless Glass Rooftop Stairway Cover
Small Frameless Glass Box Rooftop Sunroom
Frameless Glass Link Extension on a Stone Cottage
Small Frameless Glass Side Extension to the Boundary Wall
A Double Storey Glass Box Extension Enclosing a Patio and Balcony
A Contemporary Space Saving Frameless Glass Rooftop Stairway Cover
A Small Frameless Glass Sunroom with Sliding Doors
Frameless Glass Open Roof Skylight Brightening Up a Kitchen-Diner
If you want even more design inspiration for your glass extension, look at our full customer project gallery. Our team of specialists will be happy to help you with your design and answer any questions you may have, as well as provide a no-obligation quote.
If you love the look of the ultra-modern and sleek frameless glass box extensions and are thinking of adding one of these premium extensions to your home, then this post will give you some inspiration. Great for linking two buildings to create a flow between them, adding a spectacular entranceway, creating space for dining and entertaining or even opening up an existing wall to add light, frameless structural glass is the epitome of versatility and will undoubtedly look impressive.
Get frameless glass extension inspiration for your own project
Look at just some examples of frameless glass boxes and glass extensions we have designed and completed for our customers:
Full width all glass kitchen dinner extension on a detached property
Period London home frameless glass sunroom extension
Glass balcony balustrade surround on a luxury country home
Courtyard frameless glass room on a luxury farmhouse
Double-storey frameless glass extension on a commercial property
Large gable-ended frameless glass link extension with double doors
Modern glass box outdoor dining room extension
Frameless glass box extension, entrance way and barn doors on a limestone barn conversion
Glass link extension between two rooms of an original farmhouse cottage
Large contemporary frameless glass entertaining space on a Georgian property
If you want even more design inspiration for your frameless glass extension, take a look at our full customer project gallery. Our team of specialists will be happy to help you with your design and answer any questions you may have, as well as provide a no-obligation quote.
