BBA Agrément Certificate
Rigid PIR insulation for warm flat roofs under built-up felt, mastic asphalt and single ply membrane waterproofing.
Powerdeck® F is a high performance rigid polyisocyanurate (PIR) foam board for use in warm flat roofs under built-up felt, mastic asphalt and approved single ply membrane waterproofing systems. It is faced both sides with a mineral coated glass tissue.
|Standard product features|
1200 x 600 mm.
When tested to BS 476-3:2004, the product achieves an FAA rating when waterproofed with a 3-layer built-up felt covered with 10mm chippings. For other specifications it is advised to contact the manufacturer of the cap sheet for fire classification details. For single ply membranes, the rating achieved will vary depending on the single ply membrane used.
Exceeds 150 kPa at yield, and suitable for loads associated with maintenance traffic. For heavier traffic, extra precautions should be taken (consult the waterproofing manufacturer for appropriate details). Care must be taken to avoid damage to boards by impact or concentrated loads during installation.
Mastic asphalt waterproofing:
An isolating layer of Type 4A sheathing felt must always be used in mastic asphalt waterproofing systems. This isolates the asphalt from movement in the substrate, allows the lateral movement of moisture vapour and warm air during installation of the asphalt and acts as a vapour pressure release in service.
Other sizes available on request.
To ensure adequate drainage the roof should have a minimum finished fall of 1:80. This may mean designing for twice the minimum finished fall to account for building inaccuracies, roof deflection and building settlement. Powerdeck® F boards are also available for tapered insulation schemes.
With increasing levels of insulation it is important to ensure the continuity of insulation at the junction of elements.
The wind uplift force exerted on the roof will vary according to geographical location, site location and building height. Reference should be made to BS 6229 for adequate bonding of the vapour control layer to the deck to help resist wind uplift. Calculations relating to the bonding and any supplementary fixings should be made with reference to BS 6399.