The detailed definition and exceptions depend on the building and the work. Check the current BSR guidance, including new work, existing buildings, changes of status and emergency or exempt work.
Confirm whether the regime applies
Use the official definitions for the building and work. Height, storeys, residential units and exclusions can all affect the answer.
- Record the measured building information and intended project. Do not decide solely from the number of floors visible from the street.
- Distinguish building control duties during work from the occupied-building regime. The responsible roles and evidence are not identical.
- Confirm the appropriate authority and required approval before starting controlled work. Obtain specialist advice where the classification is uncertain.
Prepare the information before construction
Allow time for design coordination and the regulator's process in the programme.
- Identify the client, principal designer and principal contractor duties relevant to the work. Keep competence and appointment records.
- Maintain the required design information, change control and construction evidence. A change in product or detail may require more than an informal site agreement.
- Give contractors clear instructions about what must not be concealed or changed without the necessary process.
Completion and occupation
Do not equate a builder's handover with permission to occupy or use the completed work.
- Follow the applicable completion-certificate and information-transfer requirements. Check any occupation restrictions with the responsible professional.
- Retain the approved information, changes, inspection evidence and completion documentation in an accessible record.
- Coordinate with the building's accountable or responsible parties so the occupied-building information reflects the actual completed work.
Example: an alteration is inside one flat
A fictional landlord assumes internal work in a flat cannot involve the higher-risk building process. Check the building and the nature of the work first, especially anything affecting structure or fire safety. The location inside a privately owned flat does not settle the approval route.
What to do
- Record height, storeys, units and use.
- Confirm the authority and application requirements before starting.
- Keep approved designs, controlled changes and completion evidence.
Evidence to keep
- Regime assessment and BSR decision
- Design, change-control and completion records
Sources and guidance
- Building control approval for higher-risk buildingsBuilding Safety Regulator · checked 20 October 2026