Part B · England · Free to use
Space separation calculator for houses
Unprotected area allowed on an elevation by distance to the relevant boundary, using Method 1 or Table 11.1.
Approved Document B Volume 1; BR 187 reference for buildings over 10 m
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Part B · Result
12 m² allowed
Method 1, Diagram 11.7.
Checks passed- Allowed unprotected area: Calculated result2.5 m to boundary12 m²
- Proposed unprotected area: Checks passed11 m²
- Method 1 is for houses and flats up to three storeys and no more than 24 m long.
Clauses this relies on
Source edition and scope
Approved Document B Volume 1; BR 187 reference for buildings over 10 m.
This is a preliminary check of the conditions shown. Confirm the edition, project circumstances and any additional requirements with your architect or building control.
A design aid, not legal advice. Checked against the Building Regulations 2010 for England; confirm with building control.