Merthyr Tydfil, South Wales Valleys
Terraced house rear extension in Merthyr Tydfil
Rear and side return extensions for terraces, with access through the house and two neighbours. We design, get the approvals for and build rear extensions for terraced houses in Merthyr Tydfil and the surrounding area, with one contract from the first survey to building control sign-off.
Merthyr Tydfil sits in the South Wales Valleys, with postcode districts including CF47 and CF48. On a Merthyr Tydfil terrace both neighbours usually need party wall notices or agreement, so we talk to them early.
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 terraced house rear extension cost in Merthyr Tydfil?
For Merthyr Tydfil we work from the Wales rate: £1,910–£3,070 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 × 4.5 m deep (13.5 m²) | £25,500–£41,500 |
| 3 m wide × 6 m deep (18 m²) | £34,500–£55,000 |
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 terraced house rear extension in Merthyr Tydfil?
The planning route for a terraced house rear extension in Merthyr Tydfil is set by Wales's householder rules and your council.
In Wales a single-storey rear extension can often be permitted development if it projects no more than 4 metres beyond the rear wall and is no more than 4 metres high. Wales has no prior approval route for deeper extensions, so anything bigger needs a householder planning application.
The Party Wall etc. Act 1996 also applies in Wales: two months' notice for work to a shared wall and one month for foundations dug close to a neighbour's building.
Conservation areas, National Parks and National Landscapes restrict permitted development in Wales, and listed buildings need listed building consent. Before any drawing we look up the property's history with the council, because earlier extensions and removed rights change the answer.
What are homes in Merthyr Tydfil like to extend?
Stone terraces along the valley floors and post-war semis higher up are typical of Merthyr Tydfil. Sloping sites are common, so floor levels and retaining walls are designed at the start.
How a terraced house rear extension in Merthyr Tydfil 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.
Paperwork handled
Planning or permitted development, Building Regulations approval, structural design and party wall notices are all handled by us.
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.
Terraced house rear extensions near Merthyr Tydfil
From Merthyr Tydfil, the nearest places we also cover are Aberdare (3.8 miles) and Mountain Ash (4.4 miles).
- Terraced house rear extension in Aberdare
- Terraced house rear extension in Mountain Ash
- Terraced house rear extension in Tredegar
- Terraced house rear extension in Treharris
- Terraced house rear extension in Rhondda
Other work in Merthyr Tydfil:
FAQ
Terraced house rear extension questions in Merthyr Tydfil
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 Merthyr Tydfil?
Yes. We apply to the council or a registered approver under the Welsh regulations and hand over the completion certificate.
Can a terrace have a two-storey rear extension?
It is possible but harder to get through planning because of the effect on both neighbours.
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.
Do I need planning permission for a rear extension in Merthyr Tydfil?
Often not for a single-storey rear extension of up to 4 metres under Welsh permitted development. Wales has no prior approval route for deeper extensions.
Can you match the brick or stone on my Merthyr Tydfil house?
We source the closest match and show you samples before ordering; reclaimed materials are often the best match on older houses.