Strange location for a roof leak

[Robert Jones]

So this is a low sloped roof with a few skylights. I took this picture looking up at the ceiling to try and offer a better look at where the leak is showing itself. The edge of the roof is a good 2-3 feet away. I am guessing skylight leak, just a weird spot that these drips are showing. Any other suggestions?

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[John Kogel]

I don't think that is all that strange.

What is strange is that a builder thought a flat roof with skylights was a good idea in Washington State. []

Water could be running along a joist to the sill. I would not try to pin down the exact entry point in a home inspection.

[kurt]

Yes, the top of the window is a common outlet. Leaks are always about flashing details, and skylites are a high probability entry.

I've never been able to competently repair these "mystery" leaks without going back to zero and working through the steps. There's no silver bullet repair for leaks.

[Garet]

I don't find it strange. Water has ways of moving through buildings in ways that we could never imagine by looking at surface finishes.

[Robert Jones]

This particular leak is at the house we purchased in July. We just had our first "rain" since about then and this showed. I am going to go up and check the flashing and try to at least apply some "tactical" caulking.

[David Meiland]

A customer of mine has a skylight leak that shows up in the exact spot. The water blows up under the skirt flashing, drips down into the rafter bay, lands on top of the rigid foam insulation that's in the bay, and then runs down to the top plate of the wall, where it then goes down between the drywall and the top plate and drips out the window head.

In your case, the same could happen, but the water is running down the upper surface of the kraft paper, or down the drywall itself.

[John Kogel]

Robert, sorry I tried to make a funny about your new house. See if you can remove the screws holding skylights to the frames. Then the thing to do is remove the skylights and make sure the flashing comes up to the top of the frame all around the outer edge. Then lay down a bead of good quality silicone caulk, and set the skylights back down on a bed of caulk. Do it carefully so none shows around the inner edge of the frame.

In my youth, I built skylights from scratch that never leaked. It is all in the flashing details, and allowing the water to drain away.

[thomop]

Hi Robert. We also come accross this kind of roof leak all the time. Personally, it is the worst roof repairs for us to try and diagnose.

Many times i have found it to be waterproofing tape around the window being incorrectly installed or not there at all. I am not too sure what you guys call this though.

Other times, it has been a leak running down the inside of the wall of a double story onto the bottom story window area.

I do hate this leak area though!

Phil

[KStaudt]

Hi Robert,

Be careful with the tactical caulk. You can easily make things worse by blocking openings designed to drain water. Kurt has it right.Start from scratch. Seldom does caulk correct the problem. I too have extensive experience designing skylights and glazed roof systems from scratch.

Show us pictures of the outside.

[KStaudt]

Hi Robert,

Be careful with the tactical caulk. You can easily make things worse by blocking openings designed to drain water. Kurt has it right.Start from scratch. Seldom does caulk correct the problem. I too have extensive experience designing skylights and glazed roof systems from scratch.

Show us pictures of the outside.