How exactly do you figure out the source of a roof leak?

[CPT Gene Mauch]

This has been leaking since we moved in in 2015. Had the roof redone in 2020 or so and it didn't stop.

There's no attic or access, it's an addition that was built in 1955 (house was built in 1940). I'm not a roofer, but it seems like that Valley is the culprit somehow. I've tried rubber sealant under the shingles that overlap the metal, but it didn't help.

Seems like I'm gonna have to tear up a bunch of roof.

 

[OK Corgi Rancher]

I feel your pain. I have a leak in our bathroom and it's driving me batty trying to figure out where it's coming from.

Once summer's over and it cools down a bit I'm putting a metal roof over the shingles. I'm hoping that solves the problem.

 

[Catt57]

Use a garden hose?

 

[Big House]

Why are there no shingles on this area? This is where your leak is coming from.

 

[yukonjack]

View attachment 492094
Why are there no shingles on this area? This is where your leak is coming from.

There are no shingles in that area because it’s a dead valley. Two opposing sloped areas of the roof meet on a flat spot instead of a regular valley. A pan is usually constructed out of sheet metal that funnels the water off of the roof.
If not constructed properly they will leak.

 

[yukonjack]

This has been leaking since we moved in in 2015. Had the roof redone in 2020 or so and it didn't stop.

There's no attic or access, it's an addition that was built in 1955 (house was built in 1940). I'm not a roofer, but it seems like that Valley is the culprit somehow. I've tried rubber sealant under the shingles that overlap the metal, but it didn't help.

Seems like I'm gonna have to tear up a bunch of roof.

If you can clear all the trash out of the dead valley and post up another picture it would help in figuring out your problem.

 

[sushi & pistols]

If you can clear all the trash out of the dead valley and post up another picture it would help in figuring out your problem.

Holy cow who "redid" your roof and why is all that debris up there? Its really not to difficult to locate leaks. If your clean off the trash and take a couple of photos I might be able to help you. Is that a metal valley?

 

[okierider]

Could be the siding laying on the roof, should be on a wall somewhere . That will definitely get the water under the shingles. Is there a half rake gable out of the pic missing siding? Dormer?

 

[Big House]

The leak is obvious. You have an area that is covered by corraded flashing that is lower than your shingles. This has to be some sort of joke.

 

[Targetshooter]

Went through a similar situation on our house around the chimney when it was new. After several attempts from local roofers, I contacted A-Best Roofing. They took one look at my issue and told me I needed a cricket. Problem solved.