Limiting air permeability for a new dwelling

8 m³/(h·m²) at 50 Pa

New dwelling air pressure test at completion

Maximum

Limiting fabric U-values for a new dwelling

Roof 0.16; wall 0.26; floor 0.18; party wall 0.20; window, roof window and door 1.60 W/(m²·K)

New dwelling, individual element limiting standard

Minimum

Residual clear cavity width with partial fill insulation

50 mm

Masonry cavity wall with partial fill insulation board

All critical dimensions · All topics

These entries are our own editorial summaries of publicly available regulation. They are not building control approval, a warranty determination, or a substitute for the full source document.

Thermal and insulation — critical dimensions

Limiting air permeability for a new dwelling

Limiting fabric U-values for a new dwelling

Residual clear cavity width with partial fill insulation