Somerset
Building Regulations for rear extensions in Somerset
Construction drawings, structural calculations and building control through to the completion certificate. Across Somerset we handle the whole rear extension: survey, drawings, the planning route, building control and the build. Towns we cover here include Bath, Weston-super-Mare and Taunton.
Somerset has Victorian terraces nearer the centre and post-war semis on the edges. Sloping gardens are frequent, which affects floor levels and steps down to the patio.
What does it cost in Somerset?
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 Somerset?
Every rear extension in England needs Building Regulations approval, whether or not planning is needed. You can use the council's building control service or a registered building control approver, by full plans (checked before work, usually within five weeks) or a building notice, and you get a completion certificate at the end.
New fabric must meet Approved Document L (2021 edition incorporating 2023 amendments): walls 0.18, roof 0.15 and floor 0.18 W/m²K, windows 1.4 W/m²K or Band B. Under the simple route, new windows, doors and rooflights should not exceed 25% of the extension floor area plus any openings removed; more glass is possible with a whole-house calculation.
Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent.
Where in Somerset 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 Somerset?
We cover 19 towns and districts in Somerset, including Bath, Weston-super-Mare and Taunton.
Who builds the extension?
Vetted building teams working under contract to us; your contract is with S&K Property Investments and Improvement Ltd.