I'm having an extension built at the moment which includes a pitched roof down to a box gutter and parapet wall. I've uploaded the section from the building regs drawings which show that the design has the roof joists on hangers and then the box gutter sat on top of the inner leaf of the cavity wall.
All the construction details I've seen online show the joists sat on top of the wall instead of against it using joist hangers like my drawings.
Cheers for any advice
All the construction details I've seen online show the joists sat on top of the wall instead of against it using joist hangers like my drawings.
The builder said he hasn't seen a roof using joist hangers like this for years but the chippie is just cracking on with it.
I don't have much confidence in the person who did our drawings (but the chippie seems good). Is this badly designed? Would it be better if the joists sat on top of the wall or does it not really matter? It does have building regs sign off so I suppose it is fine. I'm just a bit worried that it doesn't seem like the usual way of doing this.Cheers for any advice