Covering Amersham
We work in Amersham (HP7) and the places around it, including Beaconsfield, High Wycombe and Rickmansworth.
Homes in the South East
Many South East homes are inter-war or post-war semis and detached houses with room for rear and side extensions, while historic town centres and villages bring conservation area and listed building controls.
What is included in an upward extension in Amersham?
The first question is whether the existing walls and foundations can carry the extra load, so we start with a structural survey. Then we design either a full first floor or a raised roof with dormers, handle planning or prior approval, and build the new storey while protecting the floor below.
- Design and planning or prior approval application
- Roof removal and temporary weather protection
- Full fit-out of the new rooms
What is the guide price for an upward extension in Amersham?
What bungalow and upward extensions typically cost. These are guide ranges; the written quote for your house replaces them.
| Bungalow and upward extensions | Guide price incl. VAT |
|---|---|
| Chalet conversion with dormers (total) | £45,000 to £85,000 |
| New first floor, standard specification | £2,200 to £2,800 per m² |
| New first floor, good specification | £2,800 to £3,300 per m² |
| New first floor, high specification | £3,300 to £3,800 per m² |
What approvals does an upward extension need in England?
In England we deal with the council’s planning team for permission or a lawful development certificate, with building control (the council or a registered building control approver) for inspections, and with neighbours under the Party Wall etc. Act 1996 where it applies.
In England, Class AA permitted development allows an extra storey on many detached and semi-detached houses built between July 1948 and October 2018, subject to a prior approval application covering design, neighbours’ amenity and other matters. Houses in conservation areas and other protected land need full planning permission, as do most chalet conversions with front dormers.
What should Amersham homeowners check first?
- Some bungalow foundations need strengthening before a storey can be added.
- The staircase takes space from the ground floor plan.
What are the steps?
- Tell us about the project. Call, use the guide price tool or send the form with a few photos and a postcode.
- Free site visit. We measure up, look at access, drains and the structure, and talk through options and budget.
- Price and paperwork. The design is priced line by line, and we submit the planning and building control applications.
- Construction and completion. One site lead co-ordinates every trade through to the building control certificate.
What people ask before starting
Do we need to move out?
Often for part of the job, while the roof is off and the new floor is formed. We plan this with you.
How long does it take?
About 12 to 24 weeks on site.
Can you visit a house in Amersham to quote?
Yes. After a short call we arrange a site visit to measure up and agree what the design needs to do, then send a written price.
Also covering
- Bungalow and upward extensions in Beaconsfield
- Bungalow and upward extensions in High Wycombe
- Bungalow and upward extensions in Rickmansworth
- Bungalow and upward extensions in Berkhamsted
Learn more about bungalow and upward extensions, or see every project we cover in Amersham.

