High Wycombe, Buckinghamshire
Rear extension planning drawings in High Wycombe
Rear extension planning drawings in High Wycombe: measured survey, design options, planning drawings and the application, handled for you. We measure the house, show you what the rules allow, price it in writing and build it.
High Wycombe and its postcode districts HP11, HP12 and HP13 are part of our Buckinghamshire coverage. For High Wycombe homes we start with a measured survey, then draw options before anything is submitted.
Book a free site visit
Tell us about the house and we'll call to arrange a free, no-obligation visit.
What do rear extension planning drawings cost in High Wycombe?
As a guide, £1,000–£2,500 including VAT for a single-storey rear extension, or £2,000–£3,500 for a two-storey scheme. A householder planning application in England costs £548 (£575 for applications made from 8 December 2026), and a lawful development certificate for proposed work costs half the householder fee. Your written price follows a measured survey and an agreed design, so it reflects your house, not an average.
Do you need planning permission for a rear extension in High Wycombe?
Planning for a rear extension in High Wycombe follows the English householder rules.
England's rules allow a rear extension of more than one storey without an application only when it is no deeper than 3 metres and at least 7 metres from the boundary opposite the rear wall, and never on designated land. Most two-storey schemes need householder planning permission.
Councils aim to decide householder applications within 8 weeks of validation, and prior approval within 42 days.
Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent. At the first visit we measure what is there now and tell you which route fits: permitted development, prior approval or a planning application.
What are homes in High Wycombe like to extend?
High Wycombe has a mix of Victorian terraces near the centre and larger Edwardian and inter-war houses further out. Clay soils across much of the South East mean deeper foundations near trees, which we plan for at the survey.
How a rear extension in High Wycombe comes together
Look round and measure
A free visit to see the back of the house, measure it, check the drains and boundaries and hear what you need.
Options and costs
We draw layout options and price each one, so the budget shapes the design rather than surprising you later.
Approvals
Permitted development check, prior approval or planning application, then Building Regulations drawings and structural calculations, plus party wall notices where they apply.
Fixed price and build
A written price for the agreed design, a start date and a named contact through the build, ending with the building control completion certificate.
Rear extension planning drawings near High Wycombe
We also build rear extensions in nearby Marlow (4.3 miles) and Beaconsfield (4.5 miles).
- Rear extension planning drawings in Marlow
- Rear extension planning drawings in Beaconsfield
- Rear extension planning drawings in Amersham
- Rear extension planning drawings in Amersham on the Hill
- Rear extension planning drawings in Burnham
Other work in High Wycombe:
FAQ
Rear extension planning drawings questions in High Wycombe
Can you match the brick or stone on my High Wycombe house?
We source the closest match and show you samples before ordering; reclaimed materials are often the best match on older houses.
How long does a rear extension take to build in High Wycombe?
Most single-storey rear extensions take 10 to 16 weeks on site and two-storey extensions 16 to 26 weeks, after design and approvals.
Can I see the design in 3D?
Yes; we produce simple 3D views so you can judge the size and light.
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.
Do I need planning permission for a rear extension in High Wycombe?
Often not for a single-storey rear extension of up to 3 metres (4 metres on a detached house) under permitted development, or up to 6 or 8 metres with prior approval, unless the house is in a conservation area or its rights have been removed.
Do you handle building control in High Wycombe?
Yes. We apply to the council or a registered building control approver and hand over the completion certificate.