Wrexham, North Wales
Semi-detached rear extension in Wrexham
For homes in Wrexham, a semi-detached rear extension is often the simplest way to gain space without moving. Single or two-storey extensions for semi-detached houses, with side access and one party wall. We take it from survey to completion certificate.
Wrexham sits in North Wales, with postcode districts including LL11, LL12 and LL13. In Wrexham we measure the attached neighbour's extension at the survey, because it often sets the sensible depth for yours.
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 Wrexham?
For Wrexham we work from the Wales rate: £1,770–£2,880 per square metre of new floor, including VAT, standard specification. Prices in Wales sit below our West Midlands baseline; sloping sites are the main variable.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4 m deep (12 m²) | £21,000–£34,500 |
| 4 m wide × 5 m deep (20 m²) | £35,500–£57,500 |
| 4 m wide × 6 m deep (24 m²) | £42,500–£69,000 |
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 semi-detached rear extension in Wrexham?
Here is how the rules in Wales apply to a semi-detached rear extension in Wrexham.
The Welsh Government's householder rules let many homes add a single-storey rear extension up to 4 metres deep and 4 metres high without a planning application. Deeper projects go through a householder application, because Wales has no prior approval route.
Welsh rules allow a two-storey rear extension without an application only where the ground floor is no deeper than 4 metres, the upper floor no deeper than 3 metres and at least 10.5 metres remains to the rear boundary. Most homeowners still apply for householder planning permission.
Conservation areas, National Parks and National Landscapes restrict permitted development in Wales, and listed buildings need listed building consent. At the first visit we measure what is there now and tell you which route fits: permitted development or a householder planning application.
What are homes in Wrexham like to extend?
Older terraces near the centre and post-war semis further out are typical of Wrexham. Sloping sites are common in Wales, so floor levels and retaining walls are designed at the start.
How a semi-detached rear extension in Wrexham 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.
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.
Semi-detached rear extensions near Wrexham
Neighbouring places we cover include Brymbo (3.4 miles) and Rhosllannerchrugog (3.8 miles).
- Semi-detached rear extension in Brymbo
- Semi-detached rear extension in Rhosllannerchrugog
- Semi-detached rear extension in Buckley
- Semi-detached rear extension in Mold
- Semi-detached rear extension in Chester
Other work in Wrexham:
FAQ
Semi-detached rear extension questions in Wrexham
Do you handle building control in Wrexham?
Yes. We apply to the council or a registered approver under the Welsh regulations and hand over the completion certificate.
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.
Can I match pebbledash or render?
Yes. Many semis are refinished with new render across the whole back elevation so old and new match.
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 a party wall agreement?
In Wales, usually yes if the extension is on or near a shared boundary or close to a neighbour's foundations. We serve the notices.
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.