Osterley, Greater London
Rear extension planning drawings in Osterley
For homes in Osterley, a rear extension is often the simplest way to gain space without moving. Measured survey, design options, planning drawings and the application, handled for you. We take it from survey to completion certificate.
Osterley and its postcode districts TW3, TW5 and TW7 are part of our Greater London coverage. Rear extension applications in Greater London are householder applications, which councils aim to decide within about eight weeks.
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 Osterley?
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. Ground conditions, glazing, the roof and how far the house is opened up move the final figure within the range.
Do you need planning permission for a rear extension in Osterley?
The planning route for a rear extension in Osterley is set by England's householder rules and your council.
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. Before any drawing we look up the property's history with the council, because earlier extensions and removed rights change the answer.
What are homes in Osterley like to extend?
Osterley is mostly 1930s semis, short terraces and post-war houses, so full-width single-storey and two-storey rear extensions are realistic on many plots. Some later estates had permitted development rights removed by condition, so we check the planning history first.
How a rear extension in Osterley 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.
Drawings and budget
Floor plans and elevations for the options, each with a guide price.
Planning and regulations
We take the design through the right planning route, then produce the construction drawings and engineer's calculations for building control.
Build and sign-off
We build to the approved drawings with regular updates, then hand over the building control completion certificate and any guarantees from suppliers.
Rear extension planning drawings near Osterley
Neighbouring places we cover include Isleworth (0.6 miles) and Hounslow (0.9 miles).
- Rear extension planning drawings in Isleworth
- Rear extension planning drawings in Hounslow
- Rear extension planning drawings in Heston
- Rear extension planning drawings in Brentford
- Rear extension planning drawings in Southall
Other work in Osterley:
FAQ
Rear extension planning drawings questions in Osterley
Do you handle building control in Osterley?
Yes. We apply to the council or a registered building control approver and hand over the completion certificate.
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.
Do I need an architect?
You need accurate drawings by someone who knows householder planning; we provide them.
Do I need planning permission for a rear extension in Osterley?
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.
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.
Can I live at home while the extension is built?
Usually yes. Most of the work is outside until the back wall is opened near the end, and that stage is screened off.