Would appreciate advice on the solution for my garage roof.

[Oranaiche]

Hi

I have a prefabricated garage with a flat roof formed from corrugated fibre sheets. There are a few spots where the roof leaks and condensation on the underside of the roof is a secondary issue. This is causing the paint to flake off which is another annoyance. I've been assured that laying a layer of glass wool insulation on top of the existing roof, topped with galvanised metal roofing sheets will solve the problem. Does anyone out there agree, or would I be better to take the old roof off and replace it? I really need some guidance.... hope you can help.

 

[^woody^]

Is this the Onduline system?

It should work as stated, but the edge detailing is important

 

[Oranaiche]

Thanks Woody. The company that provided this advice to me plan to use profiled, galvanised roof sheets with a plastisol finish. I am reassured to see your thoughts that in principle, their approach is sound.

They did say that the roof sheet would be long enough to be laid in one continuous piece which sounded good to me, minimising overlaps/joints.