Which is stronger Z purlin or C purlin?
Subsequently, one may also ask, what is Z purlin used for?
Z purlins or zed purlins are horizontal beams that are designed to form the roof and wall joists of a building shell structure (also view our C section purlins page). They sit between the roofing sheets and the building, acting as a support for the sheet to ensure it is firmly attached and safely in place.
Hereof, how thick should purlins be?
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. Exact requirements will vary, but as a rough guide, this is a good rule of thumb to follow.
A purlin is used to “reduce the length of the rafter”. So if the span of the rafter is within the allowable limits no purlin is needed. So at every 4' a minimum 2x4 should be run parellel with the rafters in the bottom third of the roof frame area and fastened to the rafters.