I'm putting a 4m bifold into a blockwork constructed single storey extension out of the back. Above it is a pitched roof, with velux and inside the ceiling is vaulted so no horizontal trusses.
I've been advised by the SE to use a RHS with plate, but I was wondering if anyone had used a Catnic or IG lintel in place? Its a Smart Visofold bifold that i'll be installing, and there is a deflection limit for the doors to operate smoothly. A heavy duty or greater one seems like it would be ideal if it will take the load, for cold bridging and weatherproofing. The SE seems reluctant to specify one though.
I've been advised by the SE to use a RHS with plate, but I was wondering if anyone had used a Catnic or IG lintel in place? Its a Smart Visofold bifold that i'll be installing, and there is a deflection limit for the doors to operate smoothly. A heavy duty or greater one seems like it would be ideal if it will take the load, for cold bridging and weatherproofing. The SE seems reluctant to specify one though.