Building Regulations – Section 5, Scotland & Part G, Northern Ireland

The Building Regulations requirements governing acoustic insulation in Scotland, Section 5, and Northern Ireland, Document G, are different from those in England and Wales.

Sound Transmission Values

Airborne Sound

For insulation on separating walls and floors the weighted standardised level difference (DnT,w), as defined in BS EN ISO 717-1:1997, must not be less than:

Impact Sound

For impact sound transmission through separating floors the weighted standardised impact sound pressure level (L’nT,w), as defined in BS EN ISO 717-2:1997, must not be more than:

The mean of the four calculated values must be no worse than that given in the “mean value” column. Where only two or three sets of measurements are possible the mean value is still achievable. Where only one set is possible the value achieved must be no worse than the mean value.