Dormer leaks can be caused from a number of issues.
Roof leaking on outer eadge.
Depending on how the roofs join you may have to cut a slot to work it in far enough.
A common cause for leakage is poor workmanship on your roof.
Ice dams block the natural flow of water down a roof.
Dig out any cracked or dry caulking that isn t properly sealing adjoining surfaces and replace with silicone caulk.
Lift up the shingle on the bottom edge to see what s under it.
There should be a starter strip which is most often simply shingles installed up side down that where installed so the seams do not line up with the seams in the shingles.
Recaulk the corner flashing if any areas have hardened caulk.
It bends around the edge of the roof channeling any moisture that penetrates the shingles away from the roof decking.
These leaks can happen even if everything on your roof is just fine.
This should cover the most leak prone areas.
Sometimes determining the source of the roof leak can be an even greater challenge.
If an inexperienced contractor didn t install the materials well leaks could occur.
The source of the roof leak on the outside of the home rarely matches where the leak appears on the inside of the home.
Ice dam leaks plague people in the snow belt.
The water begins to back up under flashings shingles tar paper etc.
If the leaking appears to be caused by ice buildup on the edges of the roof this likely will need to be handled by a professional ice removal crew.
Metal drip edge flashing is an important element of any roofing edge.
This leads to a good deal of frustration for the homeowner who is attempting to repair it.
It should overlap another piece of ice and water barrier laid below all the way down to the roof edge.
Then reshingle sliding metal step flashing behind the fascia board the trim behind the gutter.
Then reshingle sliding metal step flashing behind the fascia board the trim behind the gutter.
This should cover the most leak prone areas.
At a bare minimum there also should be tar paper under the starter and shingles.
Depending on how the roofs join you may have to cut a slot to work it in far enough.
It should overlap another piece of ice and water barrier laid below all the way down to the roof edge.
Worn out flashing or missing sealant can also cause roof leaks around dormers.
A roof leak at the edge of a dormer can allow a lot of water to enter your home.
Rotten or missing trim or siding can allow water to leak behind flashing and into your roof.