We have a flat roof (very low slope) made from gravel and tar, it's a little roof over the porch of the house. When it's raining, the water leaks under the soffit on the right corner, where is the less elevated part. There was almost no water that went into the gutter. I removed the loose gravel to see what was going on and I discovered a pothole in the asphalt. I spilled water in it and the water exited by the soffit, it did not overflow over the flashing in the gutter. I noticed that the gravel was loose everywhere in the roof perimeter leaving a clear gap under the flashing and the roof membrane. I started to patch some of the big gaps with plastic cement. I finally applied a non fibrous coating over some part of the joint that has smaller gap thinking that it will do the job. Then,the liquid coating was "swallowed" under the flashing and fell in the gutter making a big mess... So my question is, should the flashing be sealed all along the perimeter, if yes, how should I do that ? Plastic cement seems to have its limits. Am I missing something? Is the water drainage is supposed to be done under the flashing to fall in the gutter and there is a problem somewhere else, like with the fascia and sheating joint ? The roof age is unknown but it is probably due to be redone. My goal is to patch it to last 2 or 3 more years because we will probably demolish this structure anyway to build something else in a near future. In the meanwhile I would like to avoid the structure to collapse or being dangerous since the wood structure may have started to rot.

Rusty part of the soffit where water is usually leaking

The pothole at the corner half patched with plastic cement

The roof with pastic cement and liquid coating applied at the corner

Gap between flashing and roof membrane that may cause leaks Flashing/Drip edge and the gutter

Other corner of the roof Other part of the roof Where the coating is actually leaking

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    When you look at flashing is there a gap to let water run into gutter all the way? Take a hose up and test to see. With that lip can not see it going any other way.It looks so wrong, Like roof not built up enough to drain out. Have you seen gutters work seem full of dirt..Can you send more pics of roof ,is any metal covered with tar. And if you seal with plastic cement you need a membrane to keep it from cracking that thick. Could cold mop it leave cans in sun to heat up and mop and brush on stiff broom, to coat it. – user101687 Jun 18 '19 at 23:55
  • It's worse than that. The goop you are applying is making a big mess, that you may have to remove when you go to repair it properly. For some reason when it comes to roofs, people are drawn "like a moth to flame" toward quick-fixes, almost always involving tar, In any other situation they would face the music and ante up for the proper repair. Are roofs considered less important than other things like A/C units or furnaces? – Harper - Reinstate Monica Jun 19 '19 at 13:48
  • @RobertMoody I added more photos. No tar over the metal parts. There is indeed a gap between flashing and roof edge to let water run into gutter. I tested with the hose and the water is getting into the gutter (where there is no patch). I have folded the flashing to look under and I saw a metal part at the end. Seems that the metal piece we saw is just the gravel stop. The real drip edge is probably under the membrane telling me that the water drainage was designed to be done under the gravel stop. It is strange that the gravel stop have been added over the membrane instead of under it. – Sam Jun 20 '19 at 1:34
  • @RobertMoody, the gutter is working despite the dirt in it. I tested it with the hose. I will see at the next rain how the water behaves. My patch was probably not correct. I was convinced that the roof membrane has been eroded and that the flashing wasn't no longer covered. However, the pothole was probably a result of erosion. I've got mixed up by the fact that a newer part of the house roof (redone less than 10 years ago) has a gravel stop under a layer of tar and gravel. I hope my patch have not made the problem worst. – Sam Jun 20 '19 at 1:49

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