Around 15% of heat loss in a building is estimated to occur through front and back doors. In an energy efficient build ensure you choose good fitting doors with low u-values, generally comprising moulded units with thermal in-fill and low u-value glazing.
The Permadoor range is crafted to create the symmetry of real wood, combining the elegance of timber appearance with the high performance benefits of a moulded doors. Doors will not dent, crack, split or splinter and will resist shrinking, swelling and warping with changes of temperature, and are supplied tested to the requirements of PAS23, PAS 24 and Secured By Design.
Install vertical cavity closers either side of door openings, screw fix the internal flange to the inner leaf of the wall. Then fix door frame into opening with the front face of the frame 20mm in front of the back face of the brickwork, use fixing tabs attached to the side of the frame and screw fixed to the inner leaf of the wall. Setting the door in this position will lower the psi value achieved at this junction.
Over the openings, to reduce the possibility of heat loss, use an insulated cavity lintel such as a Catnic Cougar, above which install a cavity tray with weep vents every 450mm.
Hints & Tips
The Code for Sustainable Homes encourages the development of Lifetime Homes where the dwelling is easily accessible by everybody. Doors play a vital role in this and the use of mobility frames is essential.
It is not just the mobility frame required for Part M of the Building Regulations. The internal floor level and the external pathway to the door must be at the correct level in comparison with the doorframes threshold.
Ensure cavity closers are installed the correct way around with the full plastic side against the external skin.
The door frame should be secured in place using fixing tabs attached to the sides of the frame, screw fixed to the inner leaf of the wall. This removes the need to fix through the frame improving thermal performance. Ensure door frame is fully sealed around the external face using silicone frame sealant.