Covering Mid Glamorgan
Our coverage across Mid Glamorgan includes Rhondda, Tonypandy, Bridgend and Merthyr Tydfil.
Homes in Mid Glamorgan
Welsh homes include long terraces built into hillsides, stone cottages and modern estates, and sloping sites often shape how and where an extension can go.
What do you get with a double-storey extension?
A double-storey extension adds new rooms on both the ground and first floor in one build, typically a larger kitchen or living space downstairs and an extra bedroom or bathroom above. Because the roof and foundations are shared, the cost per square metre is usually lower than a single-storey extension.
- Measured survey, design and planning drawings
- Structural engineer’s design and calculations
- Windows, insulation, plastering, electrics and plumbing
What will a double-storey extension cost?
What double-storey extensions typically cost. These are guide ranges; the written quote for your house replaces them.
| Double-storey extensions | Guide price incl. VAT |
|---|---|
| Standard specification | £2,400 to £2,900 per m² |
| Good specification | £2,900 to £3,400 per m² |
| High specification | £3,400 to £3,850 per m² |
Planning and building rules in Mid Glamorgan
Planning decisions in Wales are made by the local council, using permitted development rules set by the Welsh Government rather than England’s. Building regulations in Wales have their own approved documents, and the Party Wall etc. Act 1996 applies to work on shared walls and boundaries.
Most two-storey extensions in Wales need householder planning permission from the council. We prepare and submit the application and deal with any questions from the planning officer.
What can change the price or programme?
- Side extensions close to a boundary are often set back or stepped down so they do not create a terraced effect.
- The new roof is tied into the old one, so roof tiles and ridge details need to match.
What are the steps?
- Send us the details. Give us a postcode, a rough idea of size and some photos, by phone, form or the guide price tool.
- Free site visit. We measure up, look at access, drains and the structure, and talk through options and budget.
- Price and paperwork. The design is priced line by line, and we submit the planning and building control applications.
- Construction and completion. One site lead co-ordinates every trade through to the building control certificate.
What people ask before starting
How long does a two-storey extension take?
Around 14 to 24 weeks on site, plus the planning period before that.
Will we need to move out?
Most people stay. The noisiest stage is when we break through into the existing first floor, which we plan for a short window.
How do I get a price for double-storey extensions in Mid Glamorgan?
Use the guide price tool for a ballpark figure, then book a visit for a fixed written price for the agreed specification.
Double-storey extensions in nearby towns
- Double-storey extensions in Rhondda
- Double-storey extensions in Tonypandy
- Double-storey extensions in Bridgend
- Double-storey extensions in Merthyr Tydfil
- Double-storey extensions in Pontypridd
- Double-storey extensions in Aberdare
- Double-storey extensions in Maesteg
- Double-storey extensions in Porthcawl
Learn more about double-storey extensions, or see every project we cover in Mid Glamorgan.

