North Wales
Two-storey rear extensions in North Wales
A larger kitchen downstairs and an extra bedroom or bathroom upstairs, under one roof. Rear extensions in North Wales: we cover 14 towns including Wrexham, Buckley and Deeside, with design, approvals and the build under one contract.
In North Wales we check the neighbours' rear windows first, because the upper floor is where most two-storey schemes win or lose planning. North Wales has Victorian terraces near the centre and semis further out. Welsh permitted development allows up to 4 metres at the rear for many houses.
How much does a two-storey rear extension cost in North Wales?
Guide prices for a two-storey rear extension in North Wales start from our Wales rate of £1,670–£2,510 per square metre, including VAT. Prices in Wales sit below our West Midlands baseline; sloping sites are the main variable.
| Size | Guide price inc VAT |
|---|---|
| 3 m × 5 m footprint, two floors (30 m²) | £50,000–£75,500 |
| 4 m × 6 m footprint, two floors (48 m²) | £80,500–£120,500 |
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 in North Wales?
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.
Where in North Wales do we work?
FAQ
Questions people ask
Does a two-storey rear extension need planning permission?
Almost always. England and Northern Ireland allow 3 metres without an application only if at least 7 metres remains to the rear boundary; Wales and Scotland are similar or stricter.
Is two-storey cheaper per square metre than single-storey?
Usually yes, because the foundations and roof are shared across twice the floor area. The total cost is higher.
Can I add an en-suite upstairs?
Yes. We plan the soil pipe route early so the bathroom sits where drainage works without boxing through the room below.
Do you cover all of North Wales?
We cover 14 towns and districts in North Wales, including Wrexham, Buckley and Deeside.
Who builds the extension?
Vetted building teams working under contract to us; your contract is with S&K Property Investments and Improvement Ltd.