Size Of Purlins For Metal Roof

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.

Size of purlins for metal roof.

Now if you are strapping the rafters 1x4 pt is usually used set at 2 intervals or closer and you double the first one at the edge of the metal. 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. Ft psf in purlin weight based on 43 g nds total purlin dead load 1 638 psf. Cee purlin lengths are cut to length from 6 45 in 1 8 increments though 20 and 25 are the most commonly chosen lengths.

Purlins are 2 by 4 feet and are installed much like metal roofing. If so you should use dimension lumber like 2x4. Roof lumber dead load 62 4 pcf 43 lbs ft. Metal mart offers a complete line of engineered purlin material.

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. Purlins are installed horizontally under metal roofs. 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.

Net variation for combned dimension. For 2x4s purlins the posts are spaced in 4 feet distance. You don t have a nailing surface on the end of a 1x4. Twist is measured with the zee laying on a flat surface under its own weight.

Roof steel dead load 63 psf steel american building components catalogue. Purlins are 2 by 4 feet and are installed much like metal roofing. They give added support to the roof and also provide a nailing surface for the end panels and drip edge. 3 009 19 1 0019 1 5 12 in.

15 3 12 in. 7 25 12 in. They are installed on top of the roof rafters with a felt underlayment or vapor barrier installed on top. Purlin spacing 23 75 in.

The typical spacing standards for residential and commercial buildings are about 1 to 2 foot. For the lighter material such as lightweight aluminum the common spacing length is 4 inches of clear gap. They give added support to the roof and also provide a nailing surface for the end panels and drip edge. For heavier material such as gage steel the metal roof purlins spacing length could go up to 4 feet.