Mid Wales
Two-storey rear extensions in Mid Wales
A larger kitchen downstairs and an extra bedroom or bathroom upstairs, under one roof. Across Mid Wales we handle the whole rear extension: survey, drawings, the planning route, building control and the build. Towns we cover here include Newtown, Brecon and Welshpool.

In Mid Wales we check the neighbours' rear windows first, because the upper floor is where most two-storey schemes win or lose planning. Older terraces near the centre and post-war semis further out are typical of Mid Wales. Sloping sites are common in Wales, so floor levels and retaining walls are designed at the start.
How much does a two-storey rear extension cost in Mid Wales?
For Mid Wales we work from the Wales rate: £1,670–£2,510 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 × 5 m footprint, two floors (30 m²) | £50,000–£75,500 |
| 4 m × 6 m footprint, two floors (48 m²) | £80,500–£120,500 |
Your written price follows a measured survey and an agreed design, so it reflects your house, not an average.
Do you need planning permission in Mid Wales?
In Wales a rear extension of more than one storey can be permitted development if the ground floor projects no more than 4 metres and the upper floor no more than 3 metres, with at least 10.5 metres to the rear boundary. It is not permitted development in conservation areas, National Parks or National Landscapes, so many double-storey schemes need a householder application.
Conservation areas, National Parks and National Landscapes restrict permitted development in Wales, and listed buildings need listed building consent.
Where in Mid 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 Mid Wales?
We cover 4 towns and districts in Mid Wales, including Newtown, Brecon and Welshpool.
Who builds the extension?
Vetted building teams working under contract to us; your contract is with S&K Property Investments and Improvement Ltd.