The complete conservatory buying guide

Conservatory Buying Guide 2026

How do I choose the right conservatory for my home?

Begin with the room’s job, not a style name. Decide whether it will be a year-round dining room, a bright sitting room, a kitchen extension, a home office or mainly a sheltered connection to the garden. That choice affects insulation, ventilation, heating, roof design and how much wall space you need. Next, look at the architecture of the original house. A restrained lean-to can suit a low eaves line; a symmetrical Edwardian or Victorian form may complement a traditional home; a slim-framed aluminium design or frameless glass box can provide a deliberate contrast.

Map the sun through the day. A south- or west-facing room usually needs more solar-control, ventilation and shading than a north-facing one, while a shaded room may benefit from higher light transmission. Measure furniture and circulation, not just the empty footprint: mark the proposed walls on the ground and allow for door swings, a dining table pulled out, radiators and a clear route to the garden. Finally, set a whole-project budget that includes groundworks, approvals, services and finishes. Compare the complete Room Outside product range, including conservatories, orangeries, oak buildings, modular extensions, garden rooms and annexes and the seasonal All-Glass Room before assuming a conventional conservatory is the answer.

What should I ask every conservatory company?

Ask who will survey, design, manufacture, install and sign off the work, and whether any part will be subcontracted. Request examples of completed projects similar in size, material and planning context to yours—not simply a gallery of unrelated best work. Ask how the company checks the existing house, ground conditions, drainage, access and the wall opening before fixing a price. You should also know who is responsible for structural calculations, planning applications, Building Regulations, inspections and completion certificates.

On performance, ask for the exact roof and side-glass specification, including whole-unit U-values, solar factor or g-value, light transmission, safety glass, warm-edge spacers and gas fill. Ask what ventilation and heating assumptions underpin any claim that the room is suitable all year. On protection, request written warranty terms for the structure, frames, sealed units, roof, hardware and workmanship; check whether any guarantee is insurance-backed and what maintenance is required to keep it valid. Finally, ask for the proposed programme, stage-payment schedule, process for variations and the named person who resolves problems after installation.

What should be included in a conservatory quote?

A useful quote should be a specification, not one large number. It should identify dimensions, drawings, frame system and colour, opening windows and doors, roof design, glass build-up, foundations, base or masonry, structural opening, drainage, electrical and heating scope, plastering, flooring, decoration, approvals, waste removal, VAT, programme and warranties. The table below shows the details that are often described differently between companies.

How do I compare quotes fairly?

Put every quote into the same headings as the table above and write “not stated” where information is missing. Compare the external dimensions and usable internal area first: two projects described as “4 × 3 metres” may use different measurement conventions. Then compare like-for-like materials and performance. A lower price may use standard glass, fewer opening vents, a different roof system, shallower assumed foundations or exclude the structural opening and internal finish. None of those choices is automatically wrong, but they should be visible.

Separate fixed price, provisional sums and allowances. Ask what evidence would change each allowance and how the price of a variation is agreed before work proceeds. Check VAT and professional or statutory fees. Compare payment timing and the protection attached to deposits, guarantees and workmanship—not just guarantee length. The best-value quote is the one that fits your brief with the fewest unresolved assumptions. Use the glass extension price guide, 2026 orangery price guide and 2026 oak building price guide as planning context, then rely on a surveyed, property-specific quotation.

What are the warning signs of a bad installer?

Be cautious when a salesperson presses for a signature before a proper survey, claims planning or Building Regulations “never apply”, will not identify the frame or glass system, or refuses to put verbal promises in the specification. A large discount that expires tonight is a sales device, not evidence of value. Other warning signs are a payment schedule heavily front-loaded before materials arrive, requests to pay an individual rather than the contracting company, no registered address, no recent comparable projects and warranties that cannot be read until after purchase.

• Vague performance claims: “energy efficient” or “self-cleaning” with no product name, U-value or glass data.
• Missing site assumptions: no written allowance for ground, drainage, access, structural openings or making good.
• Approval shortcuts: advice based only on size, without checking the property type, original house or local restrictions.
• Unclear responsibility: nobody named for design, survey, Building Control, snagging and aftercare.
• Unverifiable protection: headline “ten-year guarantee” with no provider, exclusions, transfer terms or claims route.
• Poor paperwork: no drawings, itemised scope, cancellation terms, variation process or realistic programme.

Trust evidence over polish. Verify company details, insurance and accreditations with the issuing bodies; speak to recent customers if possible; and ask how one difficult project was resolved. A credible installer will explain limitations and trade-offs as clearly as benefits. Room Outside’s design and build process shows the stages you should expect from consultation through installation and aftercare.

uPVC, aluminium, timber or oak — how to decide

Material affects proportions, maintenance and character, but the complete system and installer matter more than a material label. Request frame samples and see completed rooms if possible; colour, joints and sightlines are easier to judge at full scale.

What size can I build without planning permission?

There is no single floor-area answer. In England, a single-storey rear conservatory can often use householder permitted development if it meets every relevant condition. The normal rear projection limit is up to 4 metres from the original rear wall for a detached house and 3 metres for other houses, with a maximum overall height of 4 metres. A larger-home-extension process can allow up to 8 metres for a detached house or 6 metres for other houses, but it requires prior approval and neighbour consultation before work starts. If the extension is within 2 metres of a boundary, the eaves limit is normally 3 metres. Extensions and other buildings must also remain within the rules governing how much of the original curtilage can be covered.

Those figures are only a screening check. Side extensions, designated land, listed buildings, flats and maisonettes, Article 4 directions, earlier extensions and conditions on previous permissions can change or remove rights. “Original house” generally means the house as it stood on 1 July 1948, or when first built if later—not the house as you bought it. Planning permission and Building Regulations are separate questions, and removing doors between the house and conservatory can change the compliance route. Check the current GOV.UK householder technical guidance, use the Planning Portal conservatory guide, and seek confirmation from your local planning authority. A Lawful Development Certificate can provide formal evidence where appropriate.

Important: this is general guidance for houses in England, not property-specific planning or legal advice. Rules differ elsewhere in the UK and can change.

How long should the process take?

A realistic programme separates decision time, approvals, manufacture and work on site. Straightforward projects may move faster, while bespoke frames, planning applications, listed buildings, complex groundworks and structural alterations extend the programme. Ask for dependencies rather than a single completion promise.

1. Brief and design: commonly two to four weeks for consultation, measured survey, options and a settled outline specification.
2. Approvals and technical design: allow several weeks or longer depending on planning, prior approval, engineering and Building Control.
3. Final survey and manufacture: often four to twelve weeks depending on material, glass, finish and factory capacity.
4. Groundworks and installation: commonly several weeks, but scale, weather, access and structural work can change this substantially.
5. Finishing, inspection and snagging: allow time for plaster to dry, flooring or decoration, commissioning, certificates and agreed corrections.

The contract should state an estimated start window, the sequence of work, what the homeowner must prepare and how delays or changes are communicated. Do not book decorators or furniture against an optimistic sales date; wait for the project manager’s confirmed programme.

What questions should I ask about glass specification?

Ask for separate specifications for roof glass and vertical glass because they face different solar, safety and loading demands. Request the whole-unit U-value: lower values indicate less heat passing through, but U-value alone does not predict summer comfort. Also ask for g-value or solar factor, which indicates how much solar energy enters, and visible light transmission, which helps explain how bright or tinted the glass may feel. The right balance depends on orientation, roof area, surrounding shade and how you use the room.

Confirm whether the units use toughened or laminated safety glass in each location, warm-edge spacer bars, low-emissivity coatings and an argon or other gas fill. Ask about roof-glass coatings, glare and UV reduction, external condensation, acoustic performance and any self-cleaning claim—including the pitch and exposure it needs to work. Check whether patterned, tinted or solar-control glass will look different between roof and sides. Finally, request the sealed-unit warranty, exclusions for thermal breakage or nickel sulphide inclusion, replacement availability and the process if a unit mists. Explore New Generation Glass, but compare its declared figures with the exact standard alternative in your quote.