Roof Purlin Wood Purlin Size And Spacing

Roof lumber dead load 62 4 pcf 43 lbs ft.

Roof purlin wood purlin size and spacing.

Twist is measured with the zee laying on a flat surface under its own weight. If you want to know how to support roof purlins they are usually supported by 2 4 or 2 6 struts or posts. This is the distance between rafter centres. For the lighter material such as lightweight aluminum the common spacing length is 4 inches of clear gap.

Net variation for combned dimension. Roof steel dead load 63 psf steel american building components catalogue. For heavier material such as gage steel the metal roof purlins spacing length could go up to 4 feet. Ft 15 23 75 12 in.

Ft psf in purlin weight based on 43 g nds total purlin dead load 1 638 psf. 3 009 19 1 0019 1 5 12 in. Purlin spacing 23 75 in. The standard of purlin length will vary anywhere between 100 to 300 mm while the thickness will vary anywhere between 1 to 3 mm.

7 25 12 in. 15 3 12 in. However engineering determines the optimal spacing between the purlins. The typical spacing standards for residential and commercial buildings are about 1 to 2 foot.

Spacing for purlins on a standard load most designs call for purlin placement at five foot intervals. The heavier the expected load is the shorter the distance between the purlins.