Cardiff and the Vale
Building Regulations for rear extensions in Cardiff and the Vale
Construction drawings, structural calculations and building control through to the completion certificate. Rear extensions in Cardiff and the Vale: we cover 6 towns including Cardiff, Barry and Penarth, with design, approvals and the build under one contract.
Cardiff and the Vale has Victorian terraces near the centre and semis further out. Welsh permitted development allows up to 4 metres at the rear for many houses.
What does it cost in Cardiff and the Vale?
As a guide, £2,500–£5,500 including VAT. Your written price follows a measured survey and an agreed design, so it reflects your house, not an average.
What approvals does it need in Cardiff and the Vale?
In Wales a rear extension needs Building Regulations approval through the council or a registered approver, and is built to the Welsh Approved Documents, which differ from England's in places, including energy efficiency.
Wales has its own Approved Document L, with targets for walls, roofs, floors and glazing similar to but not identical with England's. Heavily glazed designs are checked with a calculation.
Conservation areas, National Parks and National Landscapes restrict permitted development in Wales, and listed buildings need listed building consent.
Where in Cardiff and the Vale do we work?
FAQ
Questions people ask
Full plans or building notice?
Full plans for most extensions: the design is checked before work starts. A building notice suits only simple jobs.
Who inspects the work?
The council's building control team or a registered building control approver (in Scotland, the council's building standards team).
What is a completion certificate?
The document confirming the work meets the regulations. Keep it; buyers' solicitors ask for it.
Do you cover all of Cardiff and the Vale?
We cover 6 towns and districts in Cardiff and the Vale, including Cardiff, Barry and Penarth.
Who builds the extension?
Vetted building teams working under contract to us; your contract is with S&K Property Investments and Improvement Ltd.