Osb Thickness For Roof Uk

The recommended minimum thickness of osb panels for timber frame walls is 12mm when the cells in the supporting frame measure up to 62 5cm on a side and 15mm for frame members spaced up to 83 3cm apart.

Osb thickness for roof uk. Thicknesses range from 5 16 to 3 4 inch and the proper one to use depends on the spacing of the rafters. Osb sold in the uk is made to comply with bs en 300 oriented strand board osb definitions classifications and specifications. For shed construction there are two commonly used grades of osb. So i will try and simplify what you need to know.

It is a long document with many parts and subsections. 18mm was initially chosen for its strength. Because of its construction some manufacturers actually make larger sheets of osb. The thickness required by josh s circumstances are good for roof snow loads of up to 70 psf again spanning 24.

Bob225 wrote why waste ply on a roof unless its rough shuttering ply 12mm wbp is perfectly fine if your feeling really tight osb 3 aka stirling board will do the trick i figured hardwood plywood would be a better choice since it s more substantial. Half inch osb is suitable for rafter spacings up to 24 inches whether or not the edges are. We have the right sized osb3 board for almost every job. However you might find that osb can better suit your needs than plywood for the roof.