Orangery extensions across Windsor
We design and build orangery extensions for houses in Windsor, with a written price once the survey and design are done and one point of contact throughout.
- Guide price in WindsorFrom £33,500 inc VAT
- PlanningSame limits as single-storey rear; glazing checked for building regs
- Build time10–16 weeks on site
- Postcode districtsSL1, SL3, SL4
What we take care of
- Foundations, walls and insulated perimeter roof
- Design of piers, roof perimeter and lantern proportions
- Heating sized for the glass area
- Opening into the main house
- Thermal calculations where glazing is generous
- Aluminium or timber lantern and full-height glazing
The lantern-to-roof ratio sets the character. A wider solid perimeter gives a calmer, more room-like space and hides downlights and speakers; a bigger lantern feels brighter but needs more care against summer heat.
Do I need planning permission in Windsor?
In England a glazed or orangery-style extension follows the same size limits as any single-storey rear extension: 3 m or 4 m without an application, or up to 6 m and 8 m through prior approval. Building regulations limit glazing to about a quarter of the new floor area plus the openings it replaces, unless whole-house calculations show the design still performs.
Before any drawing is finalised we check whether the house is listed, in a conservation area or subject to an Article 4 direction.
Building regulations approval is separate from planning. In England you can use the council's building control team or a registered building control approver; a full plans application gets the drawings checked before work starts, and the inspector signs the work off with a completion certificate.
Building over or within 3 m of a public sewer needs the water company's consent, usually through a build-over agreement, before the foundations go in.
Applications are decided by the local planning authority (your district, borough or unitary council).
Extensions in and around Windsor
Our survey diary covers Windsor, including SL1, SL3, SL4. The same team covers Slough (2 miles), Maidenhead (6 miles), Bracknell (8 miles), Wokingham (11 miles), all within easy reach.
Egham, in Surrey, is roughly 4 miles from Windsor and also on our list. Homes across the South East range from Victorian terraces in the older town centres to large detached houses on the edges, so the right extension type varies street by street.
What should I budget for an orangery extension in Windsor?
These guide figures apply our South East England adjustment (×1.12) to national rates. They include VAT at 20% and cover the build itself; design and council fees are listed separately.
Typical rates in Windsor: £2,690 to £5,040 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 4 m 12 m² | £33,500 – £41,000 | £37,500 – £47,500 | £45,500 – £60,500 |
| 4 m × 4 m 16 m² | £43,000 – £52,000 | £50,000 – £63,000 | £60,500 – £81,000 |
| 4 m × 6 m 24 m² | £64,500 – £78,000 | £75,000 – £94,500 | £91,000 – £121,000 |
Want a range for your exact size? The guide-price tool takes about a minute.
From first visit to completion
Site visits are free and there is no obligation. Where drawings are needed, the design stage is priced in writing before it starts.
Free site visit
A designer visits, takes measurements and photos, and discusses layouts, budget and timing with you.
Design and approvals
We draw the design, agree it with you and handle planning or permitted development checks and building regulations.
Fixed written price
We confirm the build price in writing, based on the approved drawings and the finishes you have chosen.
Build and sign-off
The build is managed from start to finish, inspected at each stage and signed off on completion.
Questions people ask about orangery extensions
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Windsor, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
How long does an orangery extension take to build in Windsor?
On site, typically 10 to 16 weeks once approvals are in place. Before that, allow 6–12 weeks design and approvals.
Will my neighbours in Windsor be involved?
If a planning application or prior approval is needed, the council notifies neighbours. If the work is on or near a shared boundary, party wall notices may also be needed.
Does an orangery need planning permission?
It follows the same size limits as other single-storey extensions. In England many fit within permitted development or prior approval; others need an application.
What is the difference between an orangery and a conservatory?
An orangery has a solid roof perimeter with a central lantern and more solid wall, so it is warmer and more like a room. A conservatory is mostly glass. Building regulations treat a heated orangery joined to the house as an extension.
Book a free site visit in Windsor
We will measure up, check the planning position and give you honest guide figures.
- Free, no-obligation site visit
- Planning route checked before you spend on drawings
- Written price once the design is agreed
- Building control sign-off at the end
Prefer to talk? Call 0800 088 6341 or .
Book a free site visit
Tell us a little about the project and we will arrange a time.