LAB964R, Issue 4, May 2014
Page 6
4
Ducting guidelines
4.1
Please refer to the dwelling’s design drawings for the proposed ducting layout.
4.2
Two 220mm x 90mm sockets are provided for connecting the ducting. Domus rigid ductwork should be
securely connected to the sockets using
Domus DDSEAL
acrylic sealant; failure to do this will cause
unnecessary air leakage and impair performance.
Important
: Using the arrows moulded into the body
of the
CMX
appliance as a guide, ensure that the direction of airflow is from the ‘wet rooms’ to the
outside.
4.3
Ducting attached to the appliance must be supported adjacent to the appliance using Domus 922
Domus 922
Domus 922
Domus 922
support clips. This is important for major maintenance or end of life replacement to ensure that
the ducting is adequately supported if the CMX
CMX
CMX
CMX body is removed.
4.4
Where ducting passes through unheated areas and voids (e.g. loft spaces) it must be insulated in order
to comply with Approved Document F of The Building Regulations.
4.5
When passing through a fire-stopping wall or fire-compartment wall,
Domus FireBrake
intumescent
duct connectors should be used in order to comply with Approved Document B of The Building
Regulations.
4.6
Alternative proprietary fire-stopping methods may be employed provided they comply with Approved
Document B of The Building Regulations.
4.7
Rigid ducting – install using the least number of fittings to minimise resistance to airflow. All duct runs
should be as short and as straight as possible for maximum performance.
4.8
Semi-rigid (Domus Radial) ducting – instructions available on request or available to download at
www.polypipe.com/ventilation
– see also 4.1.
4.9
The stale extract air must be expelled to the exterior of the property. If expelled through a wall, a
Domus 905
airbrick should be fitted. If expelled through the roof a
Domus 4411
universal roof terminal
should be fitted or a proprietary roof terminal designed for mechanical ventilation with a free area of at
least 15175mm².
4.10
Further details regarding installation can be found in the 2010 Domestic Ventilation Compliance Guide.
