(1) Cost of transportation. Galvanized Z-shaped purlins can be placed on top of each other, so the cost of z-shaped purlins is much lower than that of galvanzied c-shape purlins when transporting the same weight. And stacking z-shaped purlins can save a lot of construction site area

(2) Through a simple comparison of the previous mechanical properties, under the same load conditions, based on the basic knowledge of structural mechanics, the cross-section size of z-shaped purlins designed as continuous beams is smaller than that of C-shaped purlins designed as simply supported beams, and  preferred z-shaped purlins have a great impact on reducing costs.

To sum up, the following two points can be obtained from actual engineering design experience:

1. When the span of roofing purlins is greater than 10 meters, high-frequency welding of light H-shaped steel should be used:

2.When the roofing and When the wall span is less than 10 meters, the rafters and z-shaped rafters each have their advantages and disadvantages. The z-shaped rafters have a wider range of use and better mechanical performance, and should be preferred. However, flat roofs and local structural treatments require the use of purlins.

Therefore, when designing a building using steel purlins, according to the actual situation of the project, z-shaped purlins should be preferentially used, and a small number of galvanzied C-shaped purlins should be configured to make the design as safe, economical and reasonable as possible.

Xiamen Shnegqian Steel Technology Co.,Ltd are avaliable to supply steel purlins to support your steel framing system project.