How Close Do You Install Perlins Under A Metal Roof

Correctly measure the spacing of furring strips for a metal roof to further decrease condensation.

How close do you install perlins under a metal roof.

You can easily go through several sheets of insulation and know that they are secure. Purlins need to follow the sides edges of the roof it is important to note that in addition to the proper spacing and doubling of purlins the valleys it is essential to include purlins along the entire perimeter of the roof. 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. Too high a snow load means the purlins fail regardless of how close together you put them because a 2 4 or 2 6 flat can only span a certain distance between trusses as snow loads increase.

He won t do it unless i put on plywood as a base he also recommended ice and water underlayment. If the roof has no roen decking and only one layer of roofing you can usually apply an insulating barrier 1 4 foam core insulation and just apply right over the existing roof. Place the first screw about 7 inches from the bottom and each subsequent screw about 18 to 24 inches apart along the vertical run. The common 4 on center design is suitable for snow loads up to 60 for most applications.

Install the roofing screws vertically along each rib in the panel. The washer under the screw head should seal to the surface of the panel without bulging or shifting. Another benefit of using staples is that they do not make a large hole when penetrating into the sheathing. Step 1 run a tape measure from end to end along the rafters of the roof to determine how many purlins will be needed for installation.

Secure the screws but do not overtighten. You will also need to install purlins around penetrations such as plumbing pipes electrical pipes and skylights among others. Purlins are 2 by 4 feet and are installed much like metal roofing. Twenty four inches is a common spacing of furring strips for a metal roof.

Do i need the plywood base. Applying right over the shingles will rub the back of the metal roof and eventually holes in the panels. The easiest and by far the quickest way to install metal roof insulation is with 1 inch staples. They give added support to the roof and also provide a nailing surface for the end panels and drip edge.

In this installation the vapor barrier is installed on the side of the insulation nearest the interior of the building.