I need to hang roof joists, for a flat roof, fixed to thermalite aerated blocks. The problem is that 1. the blocks (440 x 215 x 100) are on top of a long span catnic lintel and are only one and a half courses high. 2. the final position of the roof joists will be below the blockwork, so they will be slung/hanging. This is because I cannot fix into the back of the catnic and this is where the roof joists have to be.
Is there a question there somewhere?
Yep are there joist hangers that can be screwed into aerated blocks that can support the roof joists which will be 150mm below their anchoring points i.e slung down
I had a similar problem last year replacing a rotten floor joist in my bathroom. Most merchants stock the pressed steel masonry-type hangers which you hook over the top of new blockwork, but these are impossible to fix to the face of a wall. The old BS6178 range of galvanised heavy-duty hangers includes a type you can bolt to the wall, but I had a hard job finding any of these. In the end I used the type with a cranked top section like this:
Peter
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.