Celotex Roof Applications
1 Pitched roof sarking
The void created by a pitched roof can be made habitable by insulating along the plane of the roof pitch with Celotex rigid PIR insulation boards. This creates a warm, potentially habitable roof space in which water pipes and tanks no longer need to be insulated.
When used over the roof structure as insulating sarking, Celotex insulation creates a warm roof structure and eliminates thermal bridging at the rafters, whilst the foil facings, used in conjunction with taped joints, provide an effective barrier to moisture vapour and air leakage. The use of a single continuous layer of insulation over the rafters thereby eliminates the risk of condensation and avoids the need for ventilation of the rafter space. Where very low U-values are required Celotex recommends a two-layer system in order to reduce the racking forces on the fasteners required to fix counter-battens to rafters. In this system, the first layer of insulation is applied as a complete layer over the rafters.
A second, thinner layer is then fitted over the first layer, between the counter-battens.
See installation guide for more details