9 Best Of What Should You Put Under A Metal Roof New Update 2021. For many applications a layer of plywood underneath your metal roofing is an unnecessary expense. Traditionally metal roofs have used standard 30-pound felt paper underlayment.
If you live in an area that gets cold in the winter and sees plenty of precipitation throughout the year then you probably should install an ice and water shield under your metal roof. When installing a metal roof over an existing roof insulate the spaces between the wood strips with rigid insulation to prevent condensation before installing the roofing. Cross purlin designs with 16 OC are sometimes called for.
It serves as a moisture barrier as well as a slip sheet.
Attached to purlins horizontal pieces of wood or metal fastened to roofing trusses are structurally sound when installed according to your roofing manufacturers instructions and local building codes. Many folks assume that in a case like this condensation occurs from outside moisture. Basically any house in Montana from Billings to Philipsburg to Zortman is going to be built this way. Mar 05 2020 Do you need an ice and water shield under metal roofing.