Ben R wrote:
Hi

We've just bought a house with a double garage with a shallow-sloping
corrugated roof (part plastic coated steel sheeting, part what looks
like fibre-glass sheeting). Water is dripping down the wooden beams of
the garage from the rain and, I think, condensation. The leaks are
caused by the bright spark who built it attaching the sheets to the
timbers at the trough of each corrugation rather than at the
crest/peak. Has anyone got any ideas on how I can solve this without
having to buy new sheeting?

Loosen or remove each fixing, slather the hole with silicone or bitumenised
roofing muck, stick a rubber washer over it and refix. That should get rid
of most of the leakage, I reckon?