Hi all, planning to use 100mm celotex to replace the current 170mm itchy nasty to make working up there cleaner and easier and make plenty of storage space. With some new bracing up there making it more difficult to get around this has become a higher priority.
Have been told by celotex that I should use 12mm ply below and above the celotex to make safe for foot traffic and storage. This works out quite expensive (doubles the price per m2) and also doesn't cope elegantly with the 22mm longitudinal and diagonal strapping currently running over the ceiling joists. I have read that some people have put celotex directly on 400mm joists (mine are 600mm) and ideally I do want the celotex to go in between the web member connections to the ceiling joists so there is uninterrupted floor (and uninterrupted insulation!) and this would need supporting somehow that I don't think I would trust ply alone to do. So with this in mind I was considering buying a load more 22x100 planks and laying them diagonally with perhaps 400mm gap between each. This way the platform will be flat, the celotex should be reasonably supported and it will be cheaper for the materials. It seems ok to stand on the 22mm planks directly where they go diagonally across 600mm joists and with the celotex the weight should be spread more evenly. I'd probably still use the 12mm ply on top.
Can anyone think of or know of a reason why this would be a bad idea (apart from it isn't exactly what celotex recommended)? I've not worked with celotex before so not sure whether it will behave well doing what I propose.
Thanks for thoughts!
Have been told by celotex that I should use 12mm ply below and above the celotex to make safe for foot traffic and storage. This works out quite expensive (doubles the price per m2) and also doesn't cope elegantly with the 22mm longitudinal and diagonal strapping currently running over the ceiling joists. I have read that some people have put celotex directly on 400mm joists (mine are 600mm) and ideally I do want the celotex to go in between the web member connections to the ceiling joists so there is uninterrupted floor (and uninterrupted insulation!) and this would need supporting somehow that I don't think I would trust ply alone to do. So with this in mind I was considering buying a load more 22x100 planks and laying them diagonally with perhaps 400mm gap between each. This way the platform will be flat, the celotex should be reasonably supported and it will be cheaper for the materials. It seems ok to stand on the 22mm planks directly where they go diagonally across 600mm joists and with the celotex the weight should be spread more evenly. I'd probably still use the 12mm ply on top.
Can anyone think of or know of a reason why this would be a bad idea (apart from it isn't exactly what celotex recommended)? I've not worked with celotex before so not sure whether it will behave well doing what I propose.
Thanks for thoughts!
