Pete's workshop build

[OPJ]

Surely the OSB would be okay if you felted over it? :shock:

I agree with what was mentioned earlier, regarding the unsuitability of rock wool insulation for the roof. Might be better to get hold of some of that foil-backed stuff which you can cut to size with a handsaw... Can't remember what it's called now! :roll: I know Adam used it in his build and he managed to save a few quid by obtaining some 'seconds' from somewhere.

It's looking very good though. I think £4,000 is still pretty cheap for a new build. I don't know if you could buy half a flat-packed timber unit for that much.

 

[PowerTool]

Wasn't the insulation Adam used Kingspan ? Polyurethane foam,foil both sides.Unfortunately,can't remember where he got the "seconds" from.

Andrew

 

[Anonymous]

Yep. Fully waterproof etc etc etc. and it goes a lovely black colour as well when it gets wet!
I live in a timber building and have used dozens of sheets of OSB, and based on experience, not what the book says, I felt first. Later this year I have to replace a sheet on my car port roof where the water got at it due to a blocked gutter. I would also point out that felting protects the roof from water penetration down the joint lines bewteen the OSB panels.
For what it's worth that is my experience.

Roy.

I agree with Roy (Rich ). I used OSB on my Garage roof and a very small leak caused an awful lot of damage to it, it just turned to mush in no time at all. OSB seems to be better when used vertically on walls.

 

[OPJ]

Kingspan! That's the one - thanks Andrew!