At Shedcad we design, engineer and manufature steel buildings. We like to stand out from our competition so we created some minimum standards that we use in our designs. Our wall girts and roof purlins are a minimum of 100 mm wide with a thickness of 1 mm. You might be surprised to know that some other companies quoting on your job are using a width of only 60 mm and a thickness of only 0.6 mm, that's a difference of 40% in width and another 40% in thickness, so you need to do your homework.
All our 150 mm wide girts and purlins have a minimum thickness of 1.5 mm, some other companies will go down to a thickness oonly 1.2 mm, that's a difference of  20%.
Our end wall posts and rafters are a minimum of 150 mm wide.  Some other companies are using a width  of only 100 mm, that's a difference of 33%.
But that's not all, all our girt/purlin to post/rafter connections are fully bolted not just screwed on.
Don't buy a brand name, buy steel, quality Australian Bluescope steel.
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