Cheshire
Building Regulations for rear extensions in Cheshire
Construction drawings, structural calculations and building control through to the completion certificate. We design and build rear extensions across Cheshire, from Warrington and Chester to Crewe, covering single-storey kitchen extensions, two-storey additions, side returns and wraparounds.

Stone and brick terraces are common around Cheshire. Where houses back onto a ginnel or alley, deliveries can come in from the rear, which makes the build tidier.
What does it cost in Cheshire?
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 Cheshire?
Planning and Building Regulations are separate in England: even a permitted development extension is inspected for foundations, drainage, structure, insulation, fire safety and ventilation, through the council or a registered building control approver, ending with a completion certificate.
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 Cheshire 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 Cheshire?
We cover 21 towns and districts in Cheshire, including Warrington, Chester and Crewe.
Who builds the extension?
Vetted building teams working under contract to us; your contract is with S&K Property Investments and Improvement Ltd.