Can my builder handle building control for me?

They can arrange inspections, but the drawings and calculations still need producing, and the legal responsibility for compliance sits with the person having the work done. A full plans approval protects you more than a verbal assurance does.

What if work was done without approval?

A regularisation application is possible for past unauthorised work, which usually involves opening up sections so the work can be inspected. It is more disruptive than doing it properly first time, but it does resolve the paperwork.

Do I need approval for a like-for-like replacement?

Repairs generally do not require approval, but replacing windows, rewiring, replacing a boiler and re-roofing all engage the regulations, typically through a competent person scheme rather than a formal application.

Is approved inspector the same as council building control?

They are alternative routes to the same statutory outcome. Either is valid; what matters is that the drawings and calculations are complete enough to be signed off.

Process · Cornwall

Building regulations, explained for people who are not builders

Planning permission decides whether you may build it. Building regulations decide whether what you build is safe, warm, ventilated and accessible. They are separate systems with separate approvals, and having one is no protection against failing the other.

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Full plans or building notice

A full plans application means the drawings and calculations are checked and approved before work starts. A building notice means work is inspected as it proceeds, with no approved drawings. Full plans costs a little more up front and removes almost all the risk of being told to take something out.

Full plans: approved drawing set, a document to price against, and certainty for your builder
Building notice: faster to start, appropriate only for very simple work
Either route ends with a completion certificate, which is what a purchaser's solicitor asks for

The parts that drive Cornish projects

Every project touches several approved documents, but a handful do most of the work in this county.

Part L — energy performance, insulation and airtightness, and the reason older detailing no longer passes
Part C — resistance to moisture, which matters disproportionately in a wet, exposed climate
Part B — fire safety, escape windows and protected stairs, decisive in loft conversions
Part F — ventilation, now closely tied to Part L because tighter buildings need designed airflow
Part H — drainage, including septic and package treatment systems on rural sites

Inspections and the certificate

Building control will inspect at set stages: excavation, foundations, damp-proof course, drainage, structural elements and completion. Missing a stage means opening work back up. The completion certificate is the document that closes the file and protects you at sale.

Frequently asked

Straight answers.

Can my builder handle building control for me?: They can arrange inspections, but the drawings and calculations still need producing, and the legal responsibility for compliance sits with the person having the work done. A full plans approval protects you more than a verbal assurance does.
What if work was done without approval?: A regularisation application is possible for past unauthorised work, which usually involves opening up sections so the work can be inspected. It is more disruptive than doing it properly first time, but it does resolve the paperwork.
Do I need approval for a like-for-like replacement?: Repairs generally do not require approval, but replacing windows, rewiring, replacing a boiler and re-roofing all engage the regulations, typically through a competent person scheme rather than a formal application.
Is approved inspector the same as council building control?: They are alternative routes to the same statutory outcome. Either is valid; what matters is that the drawings and calculations are complete enough to be signed off.

Need a building regulations package?

Tell us the project and whether you already have a builder — we will scope the pack accordingly.

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