High Wycombe, Buckinghamshire
Two-storey rear extension in High Wycombe
A larger kitchen downstairs and an extra bedroom or bathroom upstairs, under one roof. If you live in High Wycombe and want to know what a two-storey rear extension would cost and whether it needs planning, start with the online guide price or a free site visit.
We cover High Wycombe (HP11, HP12 and HP13) as part of our Buckinghamshire work. Two-storey rear extensions suit semi-detached houses in High Wycombe best, where the extra bedroom matters as much as the bigger kitchen.
Book a free site visit
Tell us about the house and we'll call to arrange a free, no-obligation visit.
How much does a two-storey rear extension cost in High Wycombe?
Guide prices for a two-storey rear extension in High Wycombe start from our South East England rate of £2,020–£3,020 per square metre, including VAT. South East prices run above our West Midlands baseline, mainly on labour rates and clay-soil foundations.
| Size | Guide price inc VAT |
|---|---|
| 3 m × 5 m footprint, two floors (30 m²) | £60,500–£90,500 |
| 4 m × 6 m footprint, two floors (48 m²) | £97,000–£145,000 |
These are guide ranges; the written quote after the survey is the figure that counts.
Do you need planning permission for a two-storey rear extension in High Wycombe?
Planning for a two-storey rear extension in High Wycombe follows the English householder rules.
A two-storey rear extension can be permitted development in England only if it projects no more than 3 metres, stays at least 7 metres from the rear boundary, matches the existing roof pitch and has obscure-glazed upper side windows. In practice most double-storey rear extensions go through a householder planning application.
Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent. We check your house's planning history and any conservation area before drawing, so the route is clear before you spend on plans.
What are homes in High Wycombe like to extend?
Around High Wycombe the housing ranges from inter-war semis to 1960s and 1970s estates with good-sized gardens. Many of the newer estates had permitted development rights removed by condition, so we check the planning history before anything is drawn.
How a two-storey rear extension in High Wycombe comes together
Free site visit
We measure the house and garden, look at the back wall, drainage and boundaries, and talk through what you want from the space.
Design and guide price
Two or three layout options with a guide price for each, so you choose the design knowing what it costs.
Planning and regulations
We take the design through the right planning route, then produce the construction drawings and engineer's calculations for building control.
Written price, then build
Once the design and approvals are in place, you get a fixed written price and programme, and we build through to sign-off.
Two-storey rear extensions near High Wycombe
From High Wycombe, the nearest places we also cover are Marlow (4.3 miles) and Beaconsfield (4.5 miles).
- Two-storey rear extension in Marlow
- Two-storey rear extension in Beaconsfield
- Two-storey rear extension in Amersham
- Two-storey rear extension in Amersham on the Hill
- Two-storey rear extension in Burnham
Other work in High Wycombe:
FAQ
Two-storey rear extension questions in High Wycombe
Who will build my extension?
Vetted building teams working under contract to us. Your contract is with S&K Property Investments and Improvement Ltd for the design and the build.
What postcode areas do you cover around High Wycombe?
Including HP11, HP12 and HP13, and the surrounding Buckinghamshire area.
Will we need to move out?
Rarely. The first-floor opening is made late in the job and sealed with temporary screens.
Can I get a price without a visit?
Our online guide-price tool gives a range in a couple of minutes. A written price needs a survey.
How much does a two-storey rear extension cost in High Wycombe?
As a guide, £2,020–£3,020 per square metre including VAT for a standard specification. For example, 3 m × 5 m footprint, two floors (30 m²): about £60,500–£90,500 at that rate. Your written price follows the survey.
Will I need a structural engineer?
Yes for the beam over the new opening and usually the foundations; we arrange them and their calculations go to building control.