Basement and cellar conversions in Mid Glamorgan

Covering Mid Glamorgan

We cover Mid Glamorgan, including Rhondda, Tonypandy, Bridgend and Merthyr Tydfil, and the towns around them.

Homes in Mid Glamorgan

Across Wales you find valley terraces, coastal towns, rural stone houses and newer estates, so access, slopes and local materials all feature in the design.

What is included in a basement conversion in Mid Glamorgan?

Everything below ground depends on keeping water out. We design the waterproofing system (usually a cavity drain membrane with a pump, or tanking) to the relevant British Standard guidance, then add insulation, ventilation, light and an escape route. New basements involve underpinning and a party wall process and are designed with a structural engineer.

Lightwells and windows for daylight and escape
Ventilation, heating and electrics
Finished floors, walls and ceilings

How much should I budget for a basement conversion?

Typical ranges for basement and cellar conversions. Ground conditions, access and specification move the final figure, which we fix in writing before work starts.

Basement and cellar conversions	Guide price incl. VAT
Existing cellar conversion	£1,900 to £3,000 per m²
New basement excavation	£4,200 to £6,600 per m²

Do you need permission for a basement conversion 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.

In Wales an existing cellar conversion usually does not need planning permission; new excavation and lightwells may.

What should Mid Glamorgan homeowners check first?

Groundwater levels drive the waterproofing design and cost.
A pump for the drainage system needs a battery back-up.

How does the project run?

Send us the details. Give us a postcode, a rough idea of size and some photos, by phone, form or the guide price tool.
Survey at your house. We look at the existing structure, services and access, and agree what the design needs to achieve.
Price and paperwork. The design is priced line by line, and we submit the planning and building control applications.
We build it. Work follows an agreed programme, with inspections at each stage and a final sign-off.

Questions about a basement conversion in Mid Glamorgan

Does a cellar conversion need planning permission?

Usually not if nothing changes outside. New basements and lightwells often do.

How do you keep a basement dry?

With a designed waterproofing system, usually a cavity drain membrane draining to a pump, sometimes combined with tanking.

How do I get a price for basement and cellar conversions 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.

Also covering

Learn more about basement and cellar conversions, or see every project we cover in Mid Glamorgan.