Clayton-le-Woods, Lancashire
Semi-detached rear extension in Clayton-le-Woods
Single or two-storey extensions for semi-detached houses, with side access and one party wall. If you live in Clayton-le-Woods and want to know what a semi-detached rear extension would cost and whether it needs planning, start with the online guide price or a free site visit.
Clayton-le-Woods sits in Lancashire, with postcode districts including PR5, PR25 and PR26. Where a Clayton-le-Woods 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 Clayton-le-Woods?
For Clayton-le-Woods we work from the North West England rate: £1,790–£2,910 per square metre of new floor, including VAT, standard specification. North West prices sit below our West Midlands baseline; access on terraced streets is the main variable.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4 m deep (12 m²) | £21,500–£35,000 |
| 4 m wide × 5 m deep (20 m²) | £35,500–£58,500 |
| 4 m wide × 6 m deep (24 m²) | £43,000–£70,000 |
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 Clayton-le-Woods?
The planning route for a semi-detached rear extension in Clayton-le-Woods is set by England's householder rules and your council.
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.
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.
England also has the larger home extension route: a single-storey rear extension of up to 6 metres on an attached house or 8 metres on a detached house, after prior approval from the council. The council notifies your neighbours and has 42 days to decide; the fee is £249 (£310 for applications made from 8 December 2026). The route is not available on designated land such as conservation areas.
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 Clayton-le-Woods like to extend?
Clayton-le-Woods has long runs of terraced houses with back yards and alleys, plus 1930s semis further out. Yard extensions on terraces are often single-storey and close to both boundaries.
How a semi-detached rear extension in Clayton-le-Woods 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.
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.
Semi-detached rear extensions near Clayton-le-Woods
From Clayton-le-Woods, the nearest places we also cover are Leyland (0.8 miles) and Chorley (3.9 miles).
- Semi-detached rear extension in Leyland
- Semi-detached rear extension in Chorley
- Semi-detached rear extension in Preston
- Semi-detached rear extension in Horwich
- Semi-detached rear extension in Darwen
Other work in Clayton-le-Woods:
FAQ
Semi-detached rear extension questions in Clayton-le-Woods
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 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.
Do you handle building control in Clayton-le-Woods?
Yes. We apply to the council or a registered building control approver and hand over the completion certificate.
Is the site visit in Clayton-le-Woods free?
Yes. We visit, measure up and talk through the options with no cost and no obligation.