I Have Recently Had a New GRP Flat Roof

Hi Steve,

I have recently had a new GRP flat roof done to my home.It was also insulated at the same time with 100mm KingSpan, which was laid on OSB-3 and a vapour barrier. Then on top of the KingSpan, another layer of OSB-3 boards, then the GRP.

Now that the roof is finished I was able take down my bathroom ceiling as it was rainwater damaged. I noticed that the KingSpan was spaced from the wall’s (external wall’s) by as much as 25mm. My query is should there be this gap between the KingSpan and the external wall’s?

I hope you can help me with this query.