In message , Chris Bacon
writes
Tim Lamb wrote:
Chris Bacon writes
Tim Lamb wrote:
I am replacing a time expired corrugated steel roof and am
considering using composite roof panels which are much heavier

Why not just replace the "corrugated iron" sheets? Last for ages,
cheap, easy to put up.
Unfortunately moist air condenses on the underside of cold steel
sheet. This is particularly apparent when such buildings house cattle
on deep litter and there is a frost.

Lay the iron over 1/2" Sterling board. This works well. Then again,
you're adding weight...

The nice thing about steel sheeting is that the ribs confer rigidity.
This allows the construction of a weatherproof roof without much
supporting structure. My trusses are 3m apart and the purlins 1.5m.
Compare this with a conventional roof!

regards

--
Tim Lamb