Building Regulations for extensions
Separate from planning permission, and much harder to avoid: Building Regulations apply to virtually every extension, including the ones that need no planning application at all.
What Building Control actually checks
- Structure — foundations, beams over new openings, and how loads reach the ground.
- Fire safety — escape routes, and what happens to the escape route from upstairs if you change the ground-floor layout.
- Insulation and energy — wall, floor and roof performance, and glazing area.
- Drainage — new connections, and building over or near a public sewer.
- Ventilation, electrics and safe glazing in the finished rooms.
The two routes
A full plans application means the council checks your drawings before work starts — slower, but you know where you stand and your builder is quoting against approved details. A building notice lets you start sooner with inspections as you go, which suits small, simple work but puts the risk on you if an inspector disagrees with something already built.
The completion certificate matters
At the end you should receive a completion certificate. Keep it: it is what a buyer’s solicitor asks for, and chasing one retrospectively years later is expensive and sometimes impossible.
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