"jerrybuilt " wrote in :


It's not a problem. If the roof leaks, it will let water in
puddling or not. In the hot summer, a pool of water on top
helps prevent the felt expanding/buckling by evaporating.
In the winter it will just freeze without being an issue.
IMO the worst thing to put on a flat roof is "reflective"
chippings, which blow off and block gutters and drains,
and are a liability when anyone is on the roof - they are
trodden into the felt and may result in pinholing. You
should wear soft-soled shoes if on felt roofs.

Thanks for the advice - I'm not quite so bothered now. I think the pros and
cons are about evenly balanced.

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Richard
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