Ruislip Manor, Greater London
Semi-detached rear extension in Ruislip Manor
We plan and build rear extensions for semi-detached houses for homeowners in Ruislip Manor. Single or two-storey extensions for semi-detached houses, with side access and one party wall. Start with a free site visit, then a written price once the design is agreed.
Ruislip Manor is covered from our Greater London round, including HA2, HA4 and HA5. Where a Ruislip Manor semi already has a small lean-to at the back, we usually replace it rather than extend it.
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 semi-detached rear extension cost in Ruislip Manor?
In Ruislip Manor, our guide for a semi-detached rear extension is £2,470–£4,030 per square metre including VAT for a 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 m deep (12 m²) | £29,500–£48,500 |
| 4 m wide × 5 m deep (20 m²) | £49,500–£80,500 |
| 4 m wide × 6 m deep (24 m²) | £59,500–£96,500 |
We put a fixed price in writing once the design is agreed, and explain any provisional sums such as foundations.
Do you need planning permission for a semi-detached rear extension in Ruislip Manor?
Planning for a semi-detached rear extension in Ruislip Manor follows the English householder rules.
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.
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.
If 3 or 4 metres is not enough, England's prior approval route allows 6 metres on a terraced or semi-detached house and 8 metres on a detached house for a single-storey rear extension. Neighbours are consulted, the council decides within 42 days, and the fee is £249, rising to £310 from 8 December 2026.
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 Ruislip Manor like to extend?
Ruislip Manor 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 semi-detached rear extension in Ruislip Manor 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.
Options and costs
We draw layout options and price each one, so the budget shapes the design rather than surprising you later.
Paperwork handled
Planning, prior approval or permitted development, Building Regulations approval, structural design and party wall notices are all handled by us.
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.
Semi-detached rear extensions near Ruislip Manor
Close by, we work in Ruislip, about 0.6 miles away, and South Ruislip, about 1.0 miles away.
- Semi-detached rear extension in Ruislip
- Semi-detached rear extension in South Ruislip
- Semi-detached rear extension in Ickenham
- Semi-detached rear extension in Northwood Hills
- Semi-detached rear extension in Pinner
Other work in Ruislip Manor:
FAQ
Semi-detached rear extension questions in Ruislip Manor
Do I need planning permission for a rear extension in Ruislip Manor?
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 Ruislip Manor?
Yes. We apply to the council or a registered building control approver and hand over the completion certificate.
How far can I extend a semi without planning?
3 metres under permitted development in England, or up to 6 metres with prior approval, outside designated land.
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.
How long does a rear extension take to build in Ruislip Manor?
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.