Metal Roofing Directly Over Plywood

So i plan to do it.

Metal roofing directly over plywood.

I just haven t found any good evidence that it would be a bad idea to use a metal roof over an unvented attic. I don t want the extra expense of the 1 x4 s if i. Align the first metal roofing panel so that it overlaps the edging by 1 2 to 3 4 of an inch and is square to the roof line. 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.

A benefit to doing it this way is that you can see if there is any rotten plywood that needs to be replaced before installing the new roof. But it seems the condensation will affect the 2x4 strapping. In this installation the vapor barrier is installed on the side of the insulation nearest the interior of the building. Be sure the larger edge is laid so that the small edge of the next panel will overlap it.

In reading online it seems wise to install a vapor barrier over the plywood to prevent condensation from getting adsorbed into the plywood from the steel roof. I was planning on putting plywood over the rafters and cross the rafters with a 2 x4 every 16 to secure the metal roof to. I wonder if it is okay to fix the metal roof panels directly to the plywood roof deck with underlayment in between or do i need to attach the panels to 1 x4 lath. Install waterproof felt over the plywood to add protection against moisture.

I have removed all the old shingles from the roof boards not plywood the roof is in great shape and have installed an ice shield over the roof. 1 remove the shingles before installing the metal roof the first way to install a metal roof over shingles is by completely removing the old shingles before installing the new metal roof. Energy efficient and available in a variety of colors that will add value to your home metal roofing is a wise choice for homeowners. The plywood should be clean and free of raised nail heads to provide a uniform deck structure for the metal.

The only thing that may impact this life expectancy would be a significant weather event or improper installation.