Musings on building a workshop and a new machine...

[Web Goblin]

If you are going to build to 2.5mts at one side anyway would you not be as well having a pitch roof? It might not be as much of a slope as you wanted but it would Still be there. The metal roof is not really that noisy and the roof sheets are screwed down on top of the outside sheet of timber anyway.
Photo below (left)shows my workshop roof. The photo on the right shows my nearly complete bike shed with the same type of roof. The roof has the outer sheet of osb, 100mm of poly insulation, then another sheet of osb inside so its well insulated for heat and sound.

[irving2008]

If you are going to build to 2.5mts at one side anyway would you not be as well having a pitch roof? It might not be as much of a slope as you wanted but it would Still be there. The metal roof is not really that noisy and the roof sheets are screwed down on top of the outside sheet of timber anyway.
Photo below (left)shows my workshop roof. The photo on the right shows my nearly complete bike shed with the same type of roof. The roof has the outer sheet of osb, 100mm of poly insulation, then another sheet of osb inside so its well insulated for heat and sound.

Yes it will be single pitched but I wanted a double pitched roof with a useful void in it, but the expemption won't let me have that and I dont want to go to the hassle of getting permission.
So the 100mm poly insulation is between the roof joists and the OSB screwed top and bottom of the joists? Did you use T&G or the plain stuff? What did you treat the OSB with before attaching the metal covering?

I was looking at using Bitumen-coated corrugated sheet like this: