Newtown, Mid Wales
Semi-detached rear extension in Newtown
Single or two-storey extensions for semi-detached houses, with side access and one party wall. We design, get the approvals for and build rear extensions for semi-detached houses in Newtown and the surrounding area, with one contract from the first survey to building control sign-off.
Newtown sits in Mid Wales, with postcode districts including SY16. Where a Newtown 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 Newtown?
In Newtown, our guide for a semi-detached rear extension is £1,770–£2,880 per square metre including VAT for a 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 Newtown?
Here is how the rules in Wales apply to a semi-detached rear extension in Newtown.
Welsh permitted development allows a single-storey rear extension of up to 4 metres in depth and 4 metres in height, subject to boundary and garden-coverage limits. There is no larger-extension prior approval scheme in 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. We check your house's planning history and any conservation area before drawing, so the route is clear before you spend on plans.
What are homes in Newtown like to extend?
Older terraces near the centre and post-war semis further out are typical of Newtown. Sloping sites are common in Wales, so floor levels and retaining walls are designed at the start.
How a semi-detached rear extension in Newtown comes together
Look round and measure
A free visit to see the back of the house, measure it, check the drains and boundaries and hear what you need.
Options and costs
We draw layout options and price each one, so the budget shapes the design rather than surprising you later.
Approvals
Permitted development check or householder planning application, then Building Regulations drawings to the Welsh Approved Documents and structural calculations, plus party wall notices where they apply.
Fixed price and build
A written price for the agreed design, a start date and a named contact through the build, ending with the building control completion certificate.
Semi-detached rear extensions near Newtown
Close by, we work in Welshpool, about 11.8 miles away, and Llandrindod Wells, about 19.3 miles away.
- Semi-detached rear extension in Welshpool
- Semi-detached rear extension in Llandrindod Wells
- Semi-detached rear extension in Oswestry
- Semi-detached rear extension in Shrewsbury
- Semi-detached rear extension in Ludlow
Other work in Newtown:
FAQ
Semi-detached rear extension questions in Newtown
Is the site visit in Newtown free?
Yes. We visit, measure up and talk through the options with no cost and no obligation.
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.
Single or two-storey on a semi?
Two-storey if you need bedrooms, single-storey if you need a bigger kitchen. Planning risk is lower for single-storey.
Do you handle building control in Newtown?
Yes. We apply to the council or a registered approver under the Welsh regulations and hand over the completion certificate.
How much does a semi-detached rear extension cost in Newtown?
As a guide, £1,770–£2,880 per square metre including VAT for a standard specification. For example, 3 m wide × 4 m deep (12 m²): about £21,000–£34,500 at that rate. Your written price follows the survey.
Can you match the brick or stone on my Newtown house?
We source the closest match and show you samples before ordering; reclaimed materials are often the best match on older houses.