Once in the attic it can follow pipes and joists for long distances before finally dripping onto your ceiling.
Roof leaks where roof meets wall.
A roof leak at the edge of a dormer can allow a lot of water to enter your home.
When each row of shingles was installed a step flashing was put next to the wall over the shingle and then covered by the next shingle row.
Avoid repairing roof leaks yourself.
This roof leaks during the snowy part of winter and during storms in the summer certainly due to poor flashing.
Four inches of the metal laps over the shingles and the remaining four inches extends up the wall.
Old holes left over from a satellite dish or antenna mounted on your roof can be a sneaky cause of leaks.
Rotten or missing trim or siding can allow water to leak behind flashing and into your roof.
Look at the flashing in all transition points where roof meets a wall or another roof plane.
Leak where addition meets house had similar situation as todd second roof on top of original on old section the flashing was under first layer of old roof.
Use the putty knife to spread the roofing cement out so that it covers the leak source at least 1 inch on all sides.
And in our experience when a single piece of flashing extends only a few inches under the shingles especially on a long roof slope and worse on a roof that happens to slope slightly towards rather than away from the abutting vertical building wall the accumulated roof drainage water near the bottom end of the roof wall intersection will overwhelm the width of the flashing and because it is not directed back out on top of successive shingle courses it leaks into the building or building.
You find these flashings where a roof climbs alongside a vertical wall.
This is key to prevent future leakage.
In the photo you can still see signs of an ice dam.
Some roof leaks happen at step flashings.
Dormer leaks can be caused from a number of issues.
Part of the flashing turns up on the wall and the other portion gets covered by the next row of shingles.
An ice dam occurs when snow melts and the water freezes when it hits the colder edges of your roof.
Let the cement dry before putting the second layer of roofing cement on the joint.
When it would rain the water would run down chimney and dormers under second layer and dump into old gutters.
Roof leaks are tricky buggers water can sneak under a broken shingle at one end and snake its way along the underlayment before seeping into your attic someplace else.
As each row of shingles is laid a step flashing is installed over the shingle next to the wall.
The soffit that meets the roof is one of the toughest areas to waterproof.
If the roof is longer than ten feet where it butts up against the house two or more pieces of flashing are overlapped and soldered to make one large continuous flashing.
You should only be able to see a tiny bit of the flashings if they were installed correctly.
