Insulating Metal Roof No Sheathing

The 3 foot roof panels will be anchored to purlins that run diagonal to the rafters.

Insulating metal roof no sheathing.

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. 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. As a place where mold can quickly grow it is important to make sure that the paper liner is placed between the insulation and the sheathing. Insulated roof assemblies can be vented or unvented.

The problem with using. There are at least two good reasons why this approach makes more sense than installing the insulation under the roof sheathing. Lay the plywood perpendicular to the roof joists and fasten it in place using galvanized or stainless steel roofing nails. Modern metal roofs are expected to last 30 years or longer.

Traditionally we ve insulated the roof panel to try and keep the temperature on the panel from reaching the dew point. I would like to avoid installing sheathing if possible extra waste but i don t want to compromise the r value of the spray foam or to have the foam ooze out between the metal panels as it expands. Insulating a new metal roof step 1 install plywood or oriented strand board osb to act as structural roof sheathing. We ll add a vapor barrier so the moist air does not flow up through the insulation and condense on the roof.

But a preinstalled membrane may be even more effective at removing condensation. The easiest and by far the quickest way to install metal roof insulation is with 1 inch staples.