Worn out flashing or missing sealant can also cause roof leaks around dormers.
Roof leak dormer valley.
Check for power lines or electrical wires attached to your roof near the dormer.
Most shingle installers will use a thick 30 lb paper as a base for the valley.
Here s a few of the defects that can cause dormers and their windows to leak.
This is one type of leak where experience can give a big advantage in locating and fixing the problem.
Dormer leaks can be caused from a number of issues.
A roof valley is very prone to leaks especially if you have an older roof.
Roof leaks are also very common in the winter when all the snow accumulating on a roof creates a potential for a roof leak to develop especially if a roof valley on your property is not properly flashed.
Even though these were previously billed as solutions for the leak a new roof and new siding did not stop the leaking.
Trying to decide if your roofs valley is leaking or some other part of your roofing is causing a leak can be tricky.
For example soak the downhill side of a chimney first then each side then the top on both sides.
Start low soaking the area just above where the leak appears in the house.
If you don t want to wait for rain to look for the leak try bringing the garden hose up on the roof.
Rotten or missing trim or siding can allow water to leak behind flashing and into your roof.
A roof leak at the edge of a dormer can allow a lot of water to enter your home.
3 deteriorated caulk around window and sill.
Isolate areas when you run the hose.
The interior walls of the dormer were often condensated and heavy rains would lead to water damage on the lower level foyer ceiling.
Place the legs of an extension ladder on level solid ground beneath the dormer where you expect to find the roof.
Dormer valleys looking for roof leaks on the outside of your house.
Most roofers that install shingles will not have rubber membranes with them to do such areas.
Most roofers that do shingles will use a heavy base paper instead of a rubber membrane.
The reason why the roof valley is such a sensitive area has to do with all the rainwater and or melting snow that accumulates and flows through the valley on its way into the gutters.
1 improperly installed or deteriorated roof to wall or roof to roof valley flashings at top back of dormer.
Valley areas are prone to leak due to the lack of using proper materials.
Run the water over the place where you think the leak might be located.
2 lack of flashing at top of trim over window.
Louis mo home had a leaking dormer shown above that was problematic for years.
