Osb comes in 4 by 8 foot sheets as does plywood but the manufacturing process allows the production of longer and wider ones.
How to sheet a roof with osb.
Avoid butting osb panels tightly.
Provide a 1 8 inch gap.
The minimum osb panel size is 24 inches in any direction and each sheet end must rest on a rafter.
Because of its construction some manufacturers actually make larger sheets of osb.
Both cdx plywood and osb tend to come in standard sheets of four foot by eight foot 4 8.
Once the area is known divide by the area of a 4 8 sheet to find how much sheathing is needed.
Leave a 3 mm 1 8 inch gap between the osb panels to allow for expansion.
Talking about plywood or osb for roofing you cannot miss the information of the cost.
Find the area of a roof.
To find the amount of plywood needed to cover a roof start by finding the area of the roof.
Multiply the length of the roof in feet by the width of the roof in feet to find the area of the roof in square feet.
For plywood it is like 5 to 10 more expensive.
Be sure the larger edge is laid so that the small edge of the next panel will overlap it.
Roof trusses must be dry when sheathing a roof with osb to prevent mold growth in the roof and coverage gaps as the trusses dry and shrink.
Lay sheets in rows with the long edge horizontal to the roof bottom.
When the grade stamp is covered by roofing the building inspector will not be able to confirm that the correct osb roofing panel was used.
Fortunately this is one issue that has primarily been standardized by the industry.
Plywood is a bit more expensive but is usually stronger and is often selected in cases where the roof covering is heavier such as for slate clay or concrete tile roofs.
Thicknesses range from 5 16 to 3 4 inch and the proper.
Install the roofing screws vertically along each rib in the panel.
Osb roof panels should always be installed with the grade stamp facing into the attic and the screened surface with the nail guide lines facing up.
It is true as the price of every osb board is around 15 20 per sheet 4 8 sizes.
It is generally believed that osb is cheaper than plywood.
Align the first metal roofing panel so that it overlaps the edging by 1 2 to 3 4 of an inch and is square to the roof line.