Insulation Board Under Metal Roofing

We ll add a vapor barrier so the moist air does not flow up through the insulation and condense on the roof.

Insulation board under metal roofing.

The problem with using. Start at the bottom of the roof and place the first piece of rigid foam insulation against the metal flashing starting at the center line. To attach the insulation you can use screws with large washers a special adhesive made for adhering foam board insulation or for smaller pieces you can seal them in with caulk or spray foam. One of the more popular methods of placing metal roofing on a home is to lay down purlins across the existing shingles.

There are two ways to do this put in firring nailing though nails are not used any more for this strips or purlins in steel frame construction on the roof to support it or place the metal roofing directly on a flat surface like foam insulation board or the roof sheathing with roof water barrier in the correct position in the layer. Traditionally we ve insulated the roof panel to try and keep the temperature on the panel from reaching the dew point. But a preinstalled membrane may be even more effective at removing condensation. Make sure that the insulation you are using is the same thickness so that the metal roof will fit better.

Foil insulation underlayment is recommended under a metal roof and in most cases the shiny side should be facing up but there s a catch. The batts are located side to side on the rafter of the roof. Both materials make a great physical barrier between the interior building and the metal roof. Nail it around the edges with roofing nails.

In this case simply lay the insulation between the purlins. Closed cell polyisocyanurate foam core. Foam board insulation is easy to cut with a circular saw with a masonry blade or scored with a utility knife and snapped like you would drywall.