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 Amersham?
In Amersham, an orangery typically costs £2,700–£3,800 per m² of floor area, including VAT at 20% (standard rate). For a typical 16 m² project that is roughly £43,000–£61,000. Building costs in the South East run about 12% above the UK average, and the figures for Amersham are adjusted to reflect that. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| Smaller project (11 m²) | £29,500–£42,000 |
| Typical project (16 m²) | £43,000–£61,000 |
| Larger project (22 m²) | £59,500–£83,500 |
| Rate per m² | £2,700–£3,800 |
What moves the price most:
- Opening into the house
- Amount and type of glazing
- Size and shape of the footprint
- Frame material and colour
A guide range is only a starting point: the guide price tool gives an instant figure for your size, and a free survey turns it into a fixed quote.
Do you need planning permission for an orangery in Amersham?
Before anything is built in Amersham, we confirm which approvals apply 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.
If the answer is not clear-cut, we can apply for formal confirmation before you commit to the build.
What we handle
Handled as part of most orangeries:
- Building control sign-off where required
- Design to suit the style of the house
- Foundations and dwarf walls or piers
- Insulated perimeter roof with internal pelmet
- Electrics, heating and plastering
- Roof lantern and glazed panels
How long does it take?
Build time is typically 8 to 12 weeks on site. Allow time beforehand for drawings and approvals, usually 6 to 12 weeks.
Building in Amersham
Commuter towns across the South East have many 1930s and post-war semis that suit rear extensions and hip-to-gable loft conversions.
Our Amersham coverage includes postcode districts HP7, and we also work in nearby places such as Chesham, Chalfont Saint Peter and Gerrards Cross.
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
Planning or permitted development confirmation, building regulations and any party wall matters.
- 04
Construction and completion
We build, put right any snags and hand over the building control certificate.
Questions about orangeries in Amersham
How much does an orangery cost in Amersham?
In Amersham, an orangery typically costs £2,700–£3,800 per m² of floor area, including VAT at 20% (standard rate). A typical 16 m² project comes to roughly £43,000–£61,000. Your fixed price depends on the survey and drawings.
Do you build orangeries in Amersham?
Yes. We build orangeries across Amersham, including postcodes HP7. Every project starts with a free home visit.
Can it be used all year?
Yes. With an insulated roof, efficient glazing and heating, an orangery is comfortable all year.
How long does it take?
Typically 8 to 12 weeks on site once approvals are in place.
Does an orangery need planning permission?
The same rules as a single-storey extension apply. Many are permitted development, depending on depth, height and your house’s location.
