What is building regulations approval, and how is it different from planning permission?
Building regulations approval confirms that work meets national construction standards for structure, fire safety, insulation, ventilation and drainage. It is separate from planning permission: planning asks whether the building may exist in that form, building control asks whether it is safe to occupy.
Building regulations approval in one paragraph
Building regulations approval confirms that work meets national construction standards for structure, fire safety, insulation, ventilation and drainage. It is separate from planning permission: planning asks whether the building may exist in that form, building control asks whether it is safe to occupy.
Legal basis: The Building Regulations 2010, with the approved documents covering Part A (structure), Part B (fire safety), Part L (conservation of fuel and power) and Part P (electrical safety).
The two routes, and which one to use
A full plans application submits the technical drawings and structural calculations for checking before work starts, and you get a decision you can rely on and a builder who can price from an approved set. A building notice starts the work with only forty-eight hours' warning and relies on site inspection to catch problems, which is faster to start and considerably more expensive when something is caught.
For anything structural — a loft conversion, a rear extension, a wall removal — full plans is the route that protects you, because it is the one that surfaces a problem while it is still a line on a drawing.
The parts that bite hardest on a London house
Part A for beam sizing and foundation design, Part B for escape from a loft conversion — which is why a third-storey conversion drives a protected stair enclosure and fire doors through the whole house — Part L for insulation in an extension, and Part K for the stair pitch that decides whether the new room is usable at all.
What happens if you skip it
Unauthorised work has no completion certificate, and the completion certificate is what a buyer's solicitor asks for. Without it a sale stalls, and the usual remedy — a regularisation application — means opening up finished work so an inspector can see what is behind it.
The local authority can also require unsafe work to be altered or removed, and there is no time limit on that where the work presents a danger.
Building regulations approval: common questions
Do I need building regulations approval if I do not need planning permission?+
Who can approve the work?+
How long does a full plans application take?+
Where building regulations approval affects the drawings
Sources
Not sure how building regulations approval applies to your property?
Send us the address and what you want to build. We will tell you which route applies before you spend anything on drawings.