New Roof leaked, then stopped leaking?

Replaced roof system on my Deck house in Ma. this summer. Roof leaked over carport after a couple of heavy downpours. I could replicate the leak with a hose directed 1/2 way up the carport. Two weeks later I could no longer demonstrate a leak. Roofer used Owens Corning Architectural Shingles, and Ice and water shield 6’ up from roof edge.
Could a leak spontaneously seal because of summer heat, ( and ? my walking on it ?

What’s the pitch? Can you provide photos? Heat welding is all I can see… but the real reason is why it leaked in the first place.

I am wondering if maybe the slope wasn’t appropriate for these shingles (you say deck house & carport & both of these lean towards a flatter sloped roof).

When you ran the hose for a leak test, were you spraying from top down, angled INTO & UP towards the gaps, sideways… ?

Maybe the shingles were laid on with only a 2" or so offset?

That is odd.


Your answer is yes. It can happen.

There is not enough information to tell you why it happened.

It may still be leaking and you just do not know it.

Send some pics of it and then we can see a little better of what you are talking about. A pic the shows the pitch of the roof is helpful.

If it is a 2/12 or lower like most carports then the roofer should have known better than to put arch shingles on the roof. They hold water on low slope roofs. SO take a pic from the drive way straight with the ground so we can see the pitch.
Above are the requested views. Thank you for your time. The pitch is 3:12. The direction of the hose stream was about 80 degrees tilted up towards center of roof, and 60 to 90 degrees to each side. The exposed part of each shingle is 5 and 1/4".

Well your roofer made a major mistake. You are not supposed to use dims on a 2/12 pitch. They will hold water with no escape. I think you saide you had oc’s shingles if so then good luck with that. The leak will come back. They have a solid sealing strip that does trap water between the shingles. The minimum i would put those shingles on a house is 4/12 but thats just me. THis really is a flat roofing solution not shingles. 3 tabs can leak on that pitch. Sales guy does not know what he is doing. He sold you shingles where a low slope application should have been used. Some will disagree but i rather do your roof and never hear from you again unless you have a referal for me.

GTP is right, 2/12 needs low slope material, not shingles.

classic demensional lowslope leak mo.
have fun chasin leaks around.

must use a three tab on that roof.

your f#@$ed.


Might not be that bad… how did you figure it was a 2/12 pitch? Looks like a 3/12…you might be okay if its nailed right.

Nailed right or not, problem is they are oc dims. arch shingles. They have a solid sealing strip. on that roof they will leak anywhere in the field for no reason other they hold water on low pitch roof. They all do but the ocs are the worst for low pitch like that.

I am embarrasses and apologize for an error. The pitch of 2:12 was over the low sloped part of the roof which has rubber roofing; the shingled part of the roof is 3:12 pitch.

Rus, don’t be embarrassed - we’re roofers & you aren’t (which is why you’re here).

3:12 Is what we generally consider the ‘minimum’ slope for a dimensional shingle & a 4:12 or better is really more advisable. Do you know if your contractor of choice did a double lap 30 # felt? This means if a roll of felt (15 # in most cases) is laid with about a 4" overlap, the thicker 30 # is laid with half of it covering the roll below which eventually gives a total of a double lapped felt layer.

Well if im not mistaken under a 4/12 pitch you are supposed to use 2 layers of 15 pound stagered for proper water shedding. Thats the code around my parts. Either way if it is leaking something is wrong along with the archs on a 3/12

good eye rooferpete4.

may be allrite indeed.