New Construction Metal Roof Installed Over Purlins

Metal roofing panels rated for architectural use attached to purlins horizontal pieces of wood or metal fastened to roofing trusses are structurally sound when installed according to your roofing manufacturer s instructions and local building codes.

New construction metal roof installed over purlins.

Measuring the outer perimeter existing profile of the roof panel skylight locations and modularity with the new metal roof rib spacing and identifying. Use 1 1 4 inch nails to cover the outline of the roof with strips of metal eave flashing also called edging. A standard retrofit sub framing system will not allow a positive attachment to the existing roof purlins. The purpose of the purlins is to provide a solid foundation for the metal roofing panels and trim to be screwed to.

For the convenience of your customers we provide installation guides and metal roofing installation how to videos to support their building projects. The topic we want to discuss today is the purlin installation. Installing a metal roof is a complicated process with many details. Metal roof purlins are installed horizontally under metal roofs.

Place corner pieces where panels will meet bends at the edge of the roofing. The spacing of your purlins depends on the expected snow and wind load. They give added support to the roof and also provide a nailing surface for the end panels and drip edge. They are installed on top of the roof rafters with a felt underlayment or vapor barrier installed on top.

Purlins are non pressure treated 1 x 4 x 12 lumber that is installed on to the roof in a specific layout pattern and screw pattern. Our metal roof and wall panels qualify for underwriters laboratories ul class a fire rating ul 90 wind uplift rating and class 4 ul impact resistance hail rating. Its use on residential projects is far less common but has been done a lot especially in rural areas. Purlins are 2 by 4 feet and are installed much like metal roofing.