• 😂

    I’m pretty sure our one year old roof will cope, 150mm PIR on 200x75 joists. It’s the fibreglass on 12mm OSB & firings I’m slightly worried about. That said I can walk on it fine so I can’t see a distributed load like that being a problem.

  • Surprisingly, there's was virtually new too.

    The OSB should be fine though - my garden office has 12mm OSB (off 400mm centers on 2 x 8) and is supporting a supposed 80+kg wet weight of sedum.

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