Brownbuilt C812 purlins (about 1974)

[Hsang]

Hello
I am looking at a roof layout(about year 1974) with C812 purlins. Has anyone any span tables or dimensions of this C812 purlin? Would appreciate your comments.

 

[JAE]

Can you provide the location of the project?

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[Hsang]

Loxton south Australia. Thanks JAE

 

[Agent666]

I used to have some tables for brownbuilt purlins but can't find them.

It's an 8" deep purlin, the 12 likely refers to 1.15mm base metal thickness metal. This is based off current 200/12 purlins being made from 1.15mm bmt metal sheet. So I'd expect if the purlin has stiffeners then it's performance might be similar to a current 200/12 purlin. If there are no stiffeners you might need to look at it from first principles.

 

[Agent666]

Note should say I'm not sure what steel grade they were back then but if comparing to current charts you would need to factor in the differences. But I now remember they were a plain Cee shape.

Brownbuilt was bought out by lysaght I believe (before my time), so their current plain Cee section range probably has similar geometry for what it's worth.

https://cdn.dcs.lysaght.com/download/lysaght-zeds-cees-purlins-and-girts-user-guide