I'm building a shed 4.8 x 3.8, with a gabled roof 1.7m. Two weeks ago i didn't even know what a purlin was, but i'm getting there. I'm after some help on approximate timber size. The timber is radiata pine. Roofing will be colorbond.

Attachment 80829

Ridge = 5 metres long (190x45 ok?)
Vertical joists = 190x45? (ie, vertically supporting the ridge in the gable, 1.7m high)
Horizontal joists = 140x45? (they won't run the full width of the shed).
Rafters = i. I was thinking of 5 rafters. (sufficient for 5m?). ii. 90x45 strong enough?
Purlins = 70x45 strong enough?

Yes, i'm still working this out. But approximations will mean my drawings don't get me laughed out of the council offices. Appreciate any advice.

Attached Images roof.bmp (90.0 KB)


Read the full thread at RenovateForum.com...