Is it possible to fit UPVC window frames with UPVC exterior sills (No concrete prestressed sill) to a partial fill cavity wall with check reveals?
If so, What supports the frame with it sitting above the cavity void? I can understand with a stone sill, that it can be sat back over the cavity and the window bears down onto it.
If so, What supports the frame with it sitting above the cavity void? I can understand with a stone sill, that it can be sat back over the cavity and the window bears down onto it.