In order for the sheets to be easily fixed to the purlins as a rough guide they should be at least 50mm wide.
Steel purlin purlin spacing for corrugated roofing.
Roof steel dead load 63 psf steel american building components catalogue roof lumber dead load 62 4 pcf 43 lbs ft.
Purlin spacing 23 75 in.
For 2x4s purlins the posts are spaced in 4 feet distance.
For 2x6s purlins the posts are spaced in 6 feet distance.
Minimum purlin size will vary according to span.
All purlin joints must be supported by a rafter.
The screws are spaced out so that every third corrugation has a screw.
The overlaps ends and sides depends upon the sloop of the roof see below.
15 3 12 in.
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.
Corrugations should run in a straight line between the highest and lowest points and at a right angle to the purlins the intermediate supports.
For the lighter material such as lightweight aluminum the common spacing length is 4 inches of clear gap.
Psf in purlin weight based on 43 g nds.
7 25 12 in.
The typical spacing standards for residential and commercial buildings are about 1 to 2 foot.
When positioned roof purlins should be spaced no further than 1 2 metres apart when using sheeting with a thickness of 0 7mm and 1 metre when using 0 5mm sheeting.
3 1 43 lbs ft.
See section on purlin girt spacing.
Corrugated sheet roofing material is widely available and easy to use.
End purlins and periphery of roof to be fixed every 2nd crest.
If you want to know how to support roof purlins they are usually supported by 2 4 or 2 6 struts or posts.
There will be four screws per screw line placed in the high of the corrugated panel.
3 009 19 1 0019 1 5 12 in.
End purlins and periphery of roof to be fixed every 2nd crest.
We do recommend it however.
Note compliance with e2 as1 is dependent on purlin spacing and gauge of roofing.
The purpose of the purlins is to provide a solid foundation for the metal roofing panels and trim to be screwed to.
However sometimes corrugated sheets are 39 wide instead of 37 wide.
If the space between posts is greater than 8 feet then brace is needed to avoid buckling.
The diagram above is a typical 37 wide panel and the spacing works out perfectly.
Do all roofing projects require purlins.
For heavier material such as gage steel the metal roof purlins spacing length could go up to 4 feet.
Purlins provide horizontal support for the sheets and form part of the framework for the building.
The typical roof structure now consists of steel i beam rafters placed approximately 10 feet this varies depending on purlin size and other variables apart with either 4 6 or 8 lightweight steel purlins installed horizontally across the rafters.
Z purlins are connected to the rafters using cleats.