Insulating Metal Roof No Sheathing

Traditionally we ve insulated the roof panel to try and keep the temperature on the panel from reaching the dew point.

Insulating metal roof no sheathing.

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. We ll add a vapor barrier so the moist air does not flow up through the insulation and condense on the roof. Insulating a new metal roof step 1 install plywood or oriented strand board osb to act as structural roof sheathing. There are lots of different ways to insulate this type of roof but one of the best methods calls for the installation of rigid foam insulation above the roof sheathing.

When the metal is eventually replaced roofs without plywood underlayment require the insulation to be replaced or repaired because it is attached to the metal. But a preinstalled membrane may be even more effective at removing condensation. You can easily go through several sheets of insulation and know that they are secure. Insulated roof assemblies can be vented or unvented.

There are at least two good reasons why this approach makes more sense than installing the insulation under the roof sheathing. 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. Lay the plywood perpendicular to the roof joists and fasten it in place using galvanized or stainless steel roofing nails. The 3 foot roof panels will be anchored to purlins that run diagonal to the rafters.

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. The easiest and by far the quickest way to install metal roof insulation is with 1 inch staples.