Having a single storey extension built which has two bifolds along the wall facing the garden. The small one can be covered with a standard thermal break catnic but the larger doors have box sectin steel columns and an RSJ over the top. The structure sits on the inner cavity and a plate is welded to the underside of the RSJ to support the outer brick wall.
What is the best approach to minimise potential condensation through to the head of the aluminium track of the bifolds?
What is the best approach to minimise potential condensation through to the head of the aluminium track of the bifolds?