Isleworth, Greater London
Terraced house rear extension in Isleworth
We plan and build rear extensions for terraced houses for homeowners in Isleworth. Rear and side return extensions for terraces, with access through the house and two neighbours. Start with a free site visit, then a written price once the design is agreed.
Isleworth sits in Greater London, with postcode districts including TW3, TW5 and TW7. On an Isleworth terrace both neighbours usually need party wall notices or agreement, so we talk to them early.
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 terraced house rear extension cost in Isleworth?
For Isleworth we work from the London rate: £2,660–£4,290 per square metre of new floor, including VAT, standard specification. London prices sit at the top of our range because of labour rates, access through the house, parking suspensions and skip licences.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4.5 m deep (13.5 m²) | £36,000–£58,000 |
| 3 m wide × 6 m deep (18 m²) | £48,000–£77,000 |
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 terraced house rear extension in Isleworth?
Here is how the rules in England apply to a terraced house rear extension in Isleworth.
Under England's householder permitted development rules you can usually add 3 metres at the back of an attached house, or 4 metres on a detached house, without a planning application, as long as the extension stays under 4 metres high and its eaves stay under 3 metres where it is within 2 metres of a boundary.
The Party Wall etc. Act 1996 applies in England: you serve notice two months before work to a shared wall, and one month before digging foundations within 3 metres (or 6 metres for deeper foundations) of a neighbour's building. Neighbours can agree in writing; if they dissent, surveyors agree an award.
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 Isleworth like to extend?
Much of Isleworth is 1920s and 1930s semis and short terraces with longer gardens than inner London, which suit full-width single-storey rear extensions. Parking suspensions, skip licences and controlled hours on residential streets shape the programme more than the build itself.
How a terraced house rear extension in Isleworth comes together
Survey visit
We visit free of charge, measure up, check access, drainage and neighbours' extensions, and note what you want the room to do.
Drawings and budget
Floor plans and elevations for the options, each with a guide price.
Paperwork handled
Planning, prior approval or permitted development, Building Regulations approval, structural design and party wall notices are all handled by us.
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.
Terraced house rear extensions near Isleworth
We also build rear extensions for terraced houses in nearby Osterley (0.6 miles) and Hounslow (0.9 miles).
- Terraced house rear extension in Osterley
- Terraced house rear extension in Hounslow
- Terraced house rear extension in Heston
- Terraced house rear extension in Brentford
- Terraced house rear extension in Richmond
Other work in Isleworth:
FAQ
Terraced house rear extension questions in Isleworth
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.
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.
How do you keep the house clean?
Dust screens, floor protection and a single protected route through the house.
Do I need planning permission for a rear extension in Isleworth?
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.
How long does a rear extension take to build in Isleworth?
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 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.