Often flashings are used at these points as well.
Flat roof leaking at edge.
The tar may work for awhile but the leak will eventually come back.
How to install an impermeable roof.
This will act as a physical water barrier.
Install a profile filler at the highest points under a ridge cap or apron flashing to stop water ingress into.
Leaks and moisture probably the most common problems with flat roofs leaks and lingering moisture are issues that can be dealt with effectively as long as you stay on top of them.
It should overlap another piece of ice and water barrier laid below all the way down to the roof edge.
It sounds like someone did some shoddy work on the last roof replacement.
While finding a leak in a flat roof is easier than on a steep sloped shingled roof leaks can still be deceiving.
Locating flat roof leaks is hard as leaks on flat roofs go in any direction unlike a sloped roof.
And that roof edge is still a problem.
Locating a flat roof leak.
Check the edge of the roof.
Flat roof leak diagnosis repair how to track down the source of leaks in a flat roof how to apply roof sealants coatings to stop roof leaks.
See if they are secure.
Flat roof repair is made more difficult.
At the gutter edge of the roof install a pre formed foam filler between the roof sheet and the gutter flashing.
Depending on how the roofs join you may have to cut a slot to work it in far enough.
Just like any roof a flat roof will develop leaks but since it s flat the water doesn t have anywhere to go but straight down.
Diagnosing the source of leaks on a flat or low slope roof.
Look for little cracks openings or breaks in seams in these flashings.
The flashing should eventually be re done or metal flashing needs to be used along with tar in the repair work.
This should cover the most leak prone areas.
Then reshingle sliding metal step flashing behind the fascia board the trim behind the gutter.