Found roof leak, but have question

[Mikepier]

Last week I posted a problem with finding a roof leak. Well I managed to get up on the roof a few days ago with a water hose, and I aimed it right at where it was leaking in the attic. Sure enough, when I went into the attic I saw water dripping, so at least I found it rightaway, as opposed to the water traveling from another spot. But even so, when I looked at the spot on the roof, I could not see any damage. I noticed that the edges of the shingles were glued down. Anotherwords the manufacturer had put a thin layer of roof cement under the edges so it would seal by itself in the sun. So I carefully lift the edges breaking the seal, and then water came out. I guess the water was somehow entering the sides and being trapped under the shingle and making its way up to the nail under it. I did this to a few shingles on my roof and noticed the same thing, water coming out from underneath. So I took some roofing cement and with a putty knife managed to cover the nails under the shingles in the spot of the leak. Last night I went to check for leaks during the rainstorm we had, so far no leaks. But has anyone ever heard of this problem? Why are the edges sealed in the first place?

[Goedjn]

They're sealed to keep the lower edge from lifting in the wind, but they're supposed to be held down with just a dot of glue on each tab, not a continuous bead.

[Mikepier]

I can't tell if its a continuous bead or just dots.But it seemed like the whole shingle was sealed down. In any event, I noticed water coming out when I lifted the shingles.

[RicodJour]

It's a continuous bead of dots. ;) The dab of roofing cement on the nail heads can fix these things a lot of times, but the real question is why is there so much water under those shingles. There should be none or close to it.

Now you have to find out why water is getting under those shingles, otherwise you're just covering up the problem. There might be some out-of-order flashing/layering near that valley termination that's shunting water under the shingles. Need to see it. Take some pictures where you did your patching and post them.

R

[DanG]

You found and treated a symptom, but you have not found the problem. The water should not ever have been under the shingle. You either have a bad flashing or a bad valley installation in the area. The one other thing that occurs to me is that you do not have enough pitch on the roof to use composition shingles. Most manufacturers require 3 in 12 minimum.

(top posted for your convenience) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Keep the whole world singing . . . . DanG (remove the sevens) [e-mail]

[Mikepier]

I'll try to post some pics soon.

[Mikepier]

By the way, forgot to mention, I went into the attic last night and still found a leak, so I guess It's back to square one.

[Mikepier]

Here are the pics. Where you see my red caulking gun is where the roof leak is in the attic. As you can see this is a split level house, and although there is an adjacent wall joining the roof, I do not think it is coming from there because there is a soffit overhang as you can see and it's pretty dry underneath there and usually does not get that wet in the rain.

[Mikepier]

Also I forgot to mention. On that area of the roof you will notice it is stained darker than the rest of the roof. Is this because there is a leak present at that location?

[RicodJour]

The stain is from that area taking longer to dry out than the rest of the roof. You said that water was coming out from underneath the shingles when you lifted them - that water would drain down slowly and keep the shingle surface moist allowing stuff to grow (stain).

shingles where that valley terminates near the end of the gutter. If they didn't flash that area correctly, you won't be able to fix it with dabs of roofing cement. That'll only get in your way later when you have to remove nails/shingles.

It's entirely possible that the shingles/flashing look fine from the surface, but that there's something wrong underneath. The first thing I'd do would be to start looking more closely at that valley termination. You may have to remove the section of gutter over the roof and pull a few shingles. Pulling shingles in colder weather is a pain in the ass as they're not very flexible and you can crack a shingle pretty easily.

Post some pictures of that valley termination with greater detail - the pictures you posted are pretty small.

R

[Mikepier]

Yeah, I was in kind of a rush taking those pictures cause I had to pick up my kid from school. Ok I'll try again.

[Mikepier]

Ok I added some close up pics to my album: I honestly do not think its coming from the valley area because I found the leak rightaway when I put the water hose over the leak spot ( where you see the red caulking gun in the picture).