Flat Roof Sheathing Thickness

The sheathing is the base you lay over the rafters that holds the roofing felt and shingles.

Flat roof sheathing thickness.

Zip system roof assembly combines our revolutionary integrated sheathing and flashing tape or liquid flashing to provide a sealed roof for protection against moisture intrusion during construction or if high winds strip the roof covering away. Roof material then covers all. Sheathing should be a minimum of 19 32 inch thick. Minimum thickness most roofs will be sheathed in plywood at least 3 8 inch thick.

Loads will vary with the. Perlite board insulation cover board per inch of thickness. 2018 international residential code. Osb roof sheathing 7 16 inch thick approximate weight.

The inch thick boards extend from the eaves just past the exterior walls where they butt up against the plywood roof sheathing. Unlike with plywood siding the plywood sheet to be used for sheathing should be at least 3 8 inch thick. Get free estimates from local roofing contractors. On the upcodes website.

That s considered to be the minimum. If your roof is more on the flatter side then it s expected to have a heavier load. Contains sections covering roof framing roof sheathing and roof ventilation. On the upcodes website.

Plywood is typically. As an example of what you can find in chapter 8 of the 2018 irc see. Apa the engineered wood association. That will suffice on a roof with rafters set 16 inches apart with minimal roof loads.

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. Roof sheathing comes in grid marked 4 by 8 foot sheets and should be installed perpendicular to the frame. The typical thickness range for sheathing is 3 8 to 3 4 inch. Installing sheathing on a flat roof is much easier than working on a peaked roof.

Steeper roofs tend to have thinner sheathing due to not much weight being applied to the roof while flat and low sloop roofs that are likely to gather weight from precipitation or people walking on it.