This prevents thermal changes and will reduce condensation.
Osb under flat roof.
Typical types of wood used for roof sheathing are oriented strand board known as osb and plywood the most popular being osb.
However you may need to consider bolstering the plywood thickness for a roof that has a higher load.
This minimum wouldn t work if you have a flat roof.
This minimum will only work if the rafters are set 16 inches apart at most and if the roof doesn t have too much load.
I m planning on building a pole barn using 3 1 2 inch schedule 40 pipe as my frame.
Most roofs are spaced at least 20 inches apart.
Oriented strand board commonly referred to as osb is a type of engineered lumber similar to particle board formed by adding adhesives and then compressing layers of wood strands.
5 thoughts on osb under steel roofing on pole buildings kamel may 3 2018 at 11 22 am.
Osb and plywood come in thicknesses ranging from 5 16 to 3 4 inch and the thickness needed for a particular roof depends on several factors including rafter spacing expected load and roof design.
If your roof is more on the flatter side then it s expected to have a heavier load.
Sheets of 7 16 inch thick with no edge support can be used in an area where the snow load is 30 pounds per square foot.
Adding osb is good when one is going to install insulation.
Rafters that are slightly farther apart might require inch or 5 8 inch thick plywood.
Odds are that if you pass a housing development of wood framed houses it will have osb oriented strand board as exterior sheathing.
A roof that lays practically flat will have a much heavier load than a steeper roof that allows rain snow and ice to roll right off.
Dear pole barn guru.
Osb comes in 4 by 8 foot sheets as does plywood but the manufacturing process allows the production of longer and wider ones.
That s considered to be the minimum.
With edge support and the same snow load 3 8 inch osb can be used.
When you count sub floors roofs and wall sheathing osb claims about 70 of the wood sheathing market in north america over plywood.
Then the top of all your purlins once osb under metal roof panels is placed will be in the same plane and the roof steel will lay flat.
Osb is widely used as roof decking material.
I found some pre made 4 inch pipe trusses.