Perlin Size For Metal Porch Roof

Move two feet down the roof and snap a horizontal chalk line.

Perlin size for metal porch roof.

Available in cee or zee shape red oxide primed or galvanized 16 14 or 12 gauge sizes from 4 up to 12 flange widths of 1 1 2 up to 4 cut to your specified lengths hole punching available load tables available for all material. For 2x4s purlins the posts are spaced in 4 feet distance. The typical spacing standards for residential and commercial buildings are about 1 to 2 foot. 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.

Do all roofing projects require purlins. The standard of purlin length will vary anywhere between 100 to 300 mm while the thickness will vary anywhere between 1 to 3 mm. Snap the third chalk line two more feet down and continue down the roof until it is covered with purlins. 20 psf x 949 1 5 psf x 12 x 949 x 11 625 2 8 x 3 0625 x 1 15 x 1 15 972 75 psi.

Net variation for combned dimension. The substructure to which the metal panels are fastened must be properly spaced and sufficiently thick to provide a roof or wall system able to meet required design loads. Install the second row of purlins just like the first cutting the end piece to fit. For the lighter material such as lightweight aluminum the common spacing length is 4 inches of clear gap.

Cee purlin lengths are cut to length from 6 45 in 1 8 increments though 20 and 25 are the most commonly chosen lengths. The purpose of the purlins is to provide a solid foundation for the metal roofing panels and trim to be screwed to. If you want to know how to support roof purlins they are usually supported by 2 4 or 2 6 struts or posts. A 2 nominal lumber thickness provides the maximum pullout values for both screws and nails when the fasteners penetrate a minimum of 1 into the wood.

For sake of discussion we will assume a minimal roof snow load of 20 psf pounds per square foot and a 4 12 roof slope. Engineered purlin metal mart offers a complete line of engineered purlin material. For heavier material such as gage steel the metal roof purlins spacing length could go up to 4 feet.