It's a common misunderstanding that planning permission covers everything a project needs. It doesn't. Building regulations approval is a completely separate legal requirement covering structural safety, fire protection, insulation, ventilation, drainage and electrical and plumbing safety, and it applies even to plenty of work that needs no planning permission at all — a loft conversion done entirely within permitted development still needs full building regulations sign-off.
Understanding how the approval process runs helps avoid the common trap of assuming planning approval was the only permission needed.
Choosing full plans or a building notice route
Full plans involves submitting detailed drawings and, where relevant, structural calculations to building control before work starts, and getting formal approval of the design before you begin. A building notice is a lighter-touch route, more common on smaller domestic jobs, where work can start with less upfront paperwork but inspections still have to be booked and passed at each stage.
Full plans suits larger or structurally complex projects because it confirms the design is acceptable before construction begins, reducing the risk of a costly change mid-build. A building notice suits straightforward, well-understood work where the extra certainty of full plans adds less value.
Structural calculations where they're needed
Any work involving a new structural opening, a beam, altered foundations, or a change to how loads are carried through the building needs calculations produced by a structural engineer, submitted either as part of full plans or provided to the building control inspector as work proceeds under a building notice.
These calculations aren't a formality — they specify beam sizes, padstone details and bearing requirements that the builder has to construct to exactly, and any site-level change from what was calculated needs checking back with the engineer rather than adjusted by eye.
Booking inspections at the right stages
Building control inspectors need to see specific stages of work before they're covered up — foundation excavations before concrete is poured, drainage before it's backfilled, structural steelwork before it's boxed in, insulation before boarding. Missing one of these means either exposing the work again for inspection or, in some cases, being unable to get sign-off at all without invasive investigation.
This is a scheduling responsibility that sits with whoever is managing the build, and it needs building into the programme rather than treated as something to arrange reactively once a trade happens to be ready.
Obtaining the completion certificate
Once all inspections are passed and the finished work meets the regulations, building control issues a completion certificate. This is the document that proves, at any future sale, that the work was carried out to a regulated standard and signed off by an independent inspector.
The certificate should be requested and kept safely with the property's paperwork — it's commonly asked for by conveyancing solicitors, and its absence can hold up or complicate a sale even where the work itself was done properly.
Local authority versus approved inspector routes
Building regulations approval can be handled either through the local authority's own building control team or through a private approved inspector, and either is a legally valid route in England. Timescales and inspection availability can differ between the two, and it's worth confirming who is being used and getting their contact details recorded in the project paperwork from the outset.
Whichever route is used, the standards being checked against are the same national Building Regulations — the choice is about service and administration, not a lower or higher bar for compliance.
Common questions
Do I need building regulations approval if I don't need planning permission?+
In most cases, yes. Building regulations and planning permission are separate systems, and a huge amount of work that's exempt from planning — like most loft conversions under permitted development — still requires full building regulations approval.
What happens if work is covered up before an inspection?+
The building control inspector may require it to be exposed again for inspection, which can mean removing plaster, boarding or backfill that's already been completed, at real cost and delay. Booking inspections ahead of each covering-up stage avoids this entirely.
How long is the completion certificate valid for?+
It doesn't expire — it's a permanent record that the work met the regulations current at the time it was carried out, and it should be kept with the property deeds indefinitely.
Get your building regulations submission handled properly
We manage building control notifications and inspections as part of the build, so nothing gets covered up before it's checked.