8.4.1.5 Building integration
MVHR systems shall be securely fixed and not adversely affect the weather resistance of the building. Issues to be taken into account include:
- weather tightness
- fixing of fan units
- fire-stopping.
8.4.1.5.1 Weather tightness#
Proprietary roof terminals should be used to ensure the weathertightness of the roof covering.
8.4.1.5.2 Fixing of fan units#
MVHR fan units should only be fixed to parts of the building capable of taking the load. Where MVHR fan units are supported by framed structures, additional components such as noggins may be required to provide a secure fixing point.
Fan units should be located, orientated, and fixed in accordance with the design, using the clips, brackets and fixings recommended by the manufacturer.
8.4.1.5.3 Fire-stopping#
The MVHR system should not adversely affect the fire performance of the building. Issues to be taken into account include:
- ensuring that the fire requirements of the building are in accordance with relevant Building Regulations
- suitable detailing of components passing through other elements of the building
- location and type of firestops to be used
- integrity of protected stairs and halls
- integrity of walls and floors.
Proprietary passive fire protection components should be suitably tested and specified to take account of the test conditions.
Last updated: 2nd January 2024