roofing at friends cottage

[sw]

Our friends cottage has developed a leak in the shingle roof of the screened porch part of their cottage. The leak isn't heavy, and is less likely to occur during a rainstorm but rather at off rain times. e.g. seems to happen each morning. The roof construction is un- insulated/exposed in this portion of the house. I look up and saw a

16" wide x 6" patch of damp plywood sheathing centered on one of the rafters.

The shingles are old but not curling. This is the only leak and it's not a heavy one. One thing I noticed is that they get a heavy dew build-up in the night time. I wasn't sure if that might be more consistent with the leak.

I didn't get on the roof to check it but might be going back in September when I will try to check it.

Any suggestions?

Thankyou in advance.

[Cwatters]

This sounds like it might be condensation rather than a leak. Is the roof space ventilated properly?

[Tom Baker]

Point of entry for the water may well be far from the area where it becomes visible. Is there a change in roof slope or a roof penetration above this point? Is there mechanical equipment or duct work in the attic? Your idea of dew as the origin is worth checking carefully. T

[AndyS]

Andy comments:

You need to locate the leak point.

If you have running water, and a hose, use that...

Start at the lowest possible place on the roof you can, which will be approx where the wet wood is, and just run the hose at that point to see if you get ingress.

Then work your way upware and sideways. Leave the hose at least a half hour at each place.. Sooner or later the spot will get wet again, and you have a better idea of where to make the repair.

Usually, stuff like this is one or two shingles. If the wood isn't rotten, it won't need to be replaced....

Good luck,

Andy in Eureka, Texas