No Sheathing Under Metal Roof

In order to avoid a hump at the transition from two layers of materials to one the notation on the building plans advises to lower the roof purlins in these areas by 7 16.

No sheathing under metal roof.

This would mean a plywood deck with some sort of building paper to handle the inevitable condensation that forms on the underside of the roofing. Polyurethane spray foam metal roof insulation. In order to add moisture barrier under metal roof you can spray the undersides of the roof by using a thick layer of polyurethane spray foam. Owners of agricultural buildings man caves and horse barns all are worried about the corrosive effects of condensation.

July 28 2017. Underlayment must also act as a secondary weather barrier in case the roof fails. The best underlayment for metal roofs. It will help you to eliminate problems that may come when the house becomes extremely cold in the winter and terribly hot in the summer.

If your home s existing shingles are pretty curled you could install a textured metal roof such as a metal shingle shake or tile directly over the curled shingles along with underlayment. How to prevent condensation under a metal roof. Traditionally metal roofs have used standard 30 pound felt paper underlayment. My understanding is that with metal roofing you absolutely have to have a drainage plain.

Here s how to fight back against the enemy within. Metal roofing panels rated for architectural use attached to purlins horizontal pieces of wood or metal fastened to roofing trusses are structurally sound when installed according to your roofing manufacturer s instructions and local building codes. Mike the pole barn guru. If you re wondering how to prevent condensation under a metal roof you re not alone.

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.