What is an orangery?

An orangery is an extension with brick or block piers, large areas of glazing and a solid perimeter roof around a central roof lantern. It sits between a conservatory and a traditional extension: brighter than an extension, warmer and more private than a conservatory.
How much does an orangery cost in Westminster?
In Westminster, an orangery typically costs £3,100–£4,400 per m² of floor area, including VAT at 20% (standard rate). For a typical 16 m² project that is roughly £49,500–£70,500. The guide for Westminster reflects typical costs in London, roughly 30% above the UK-wide figure. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| Smaller project (11 m²) | £34,000–£48,500 |
| Typical project (16 m²) | £49,500–£70,500 |
| Larger project (22 m²) | £68,000–£97,000 |
| Rate per m² | £3,100–£4,400 |
The main things that change the cost:
- Heating and flooring
- Frame material and colour
- Amount and type of glazing
- Size and shape of the footprint
Your exact price depends on the survey and drawings. The guide price tool gives a quick range in the meantime.
Do you need planning permission for an orangery in Westminster?
Here is how the rules work for an orangery in England. In England a single-storey rear extension is often permitted development: broadly up to 3 metres deep on a semi-detached or terraced house and 4 metres on a detached house, no higher than 4 metres, with eaves no higher than 3 metres within 2 metres of a boundary, and covering no more than half the garden. The larger home extension scheme allows up to 6 or 8 metres if you notify the council first and neighbours have a chance to comment. In conservation areas, National Parks and National Landscapes the larger home extension route, side extensions and cladding are not permitted development. Flats and houses whose rights have been removed need a planning application, and listed buildings need listed building consent.
Building regulations approval comes from the council’s building control service or a registered building control approver. The work is inspected at key stages, such as foundations, drainage and insulation, and a completion certificate is issued at the end.
At the survey we check your house’s planning history and any restrictions, and tell you which route applies.
What we handle
On a typical orangery we handle:
- Electrics, heating and plastering
- Foundations and dwarf walls or piers
- Building control sign-off where required
- French, sliding or bifold doors
- Design to suit the style of the house
- Roof lantern and glazed panels
How long does it take?
The build itself usually takes 8 to 12 weeks on site. Design and approvals come first and typically take 6 to 12 weeks, depending on the approval route.
Building in Westminster
Space is at a premium in London, so homeowners often build out into the side return or up into the roof rather than move.
Westminster sits in Greater London, in central London. We cover the whole of Westminster, including postcodes SW1.
How it works
- 01
Visit and measured survey
A free visit to understand the project, check access and take measurements.
- 02
Design and pricing
Design options, then a fixed quote based on the chosen drawings and specification.
- 03
Approvals in place
We handle planning, building control and neighbour notices before work starts.
- 04
Build and sign-off
We run the build to a written programme and hand over the completion certificate.
Questions about orangeries in Westminster
Who approves an orangery in Westminster?
Planning matters in Westminster go to the council covering your address, and the work needs building control approval. We prepare and submit the applications for you.
Can an orangery replace a conservatory?
Yes. We can remove an old conservatory and build an orangery on new or upgraded foundations.
How much does an orangery cost in Westminster?
In Westminster, an orangery typically costs £3,100–£4,400 per m² of floor area, including VAT at 20% (standard rate). A typical 16 m² project comes to roughly £49,500–£70,500. Your fixed price depends on the survey and drawings.
Does an orangery need building regulations approval?
If it is open to the house or does not meet the conservatory exemption, yes. Most orangeries are treated as extensions and need building control approval, which we arrange.
What is the difference between an orangery and a conservatory?
An orangery has a solid roof around a central lantern and more brickwork, while a conservatory is mostly glazed. Orangeries are usually warmer in winter and cooler in summer.
