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. Usually 400 450 or 600mm but any value can be used up to 610mm max. For the lighter material such as lightweight aluminum the common spacing length is 4 inches of clear gap. Net variation for combned dimension.

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. Ft psf in purlin weight based on 43 g nds total purlin dead load 1 638 psf. 7 25 12 in.

For 2x4s purlins the posts are spaced in 4 feet distance. The standard of purlin length will vary anywhere between 100 to 300 mm while the thickness will vary anywhere between 1 to 3 mm. 3 1 43 lbs ft. 15 3 12 in.

Ft 15 23 75 12 in. Spacing for purlins on a standard load most designs call for purlin placement at five foot intervals. 3 009 19 1 0019 1 5 12 in. Purlin spacing 23 75 in.

The heavier the expected load is the shorter the distance between the purlins. The typical spacing standards for residential and commercial buildings are about 1 to 2 foot.