Most roofing materials are designed to work under the influence of gravity.
Roof leak after snow.
The cold weather turns the super chilled water to ice and the ice pack begins to get thicker and thicker creating a dam quite like hoover dam but a much smaller.
Heat leaking up from your home is melting the snowpack in the tight roof canyon.
Likewise a heavy blanket of snow can hide the significance of an ice dam making it hard to ascertain it s size.
An ice dam occurs when snow melts and the water freezes when it hits the colder edges of your roof.
The roof leaked a few days after a foot of snow had fallen.
Worn out flashing or missing sealant can also cause roof leaks around dormers.
This keeps the warm air in and the roof at a constant temperature thus eliminating melting snow and roof leaks from occurring.
It was warm enough for the snow to melt during the day but it would drop below freezeing at night.
Rotten or missing trim or siding can allow water to leak behind flashing and into your roof.
Protection for the perishable areas of your roof.
When i checked the roof i saw all the snow had fallen off the two story roof and landed on the addition.
If you have a low slope roof area accumulations as little as 1 thick can cause problems.
In the photo you can still see signs of an ice dam.
The steeper your roof pitch the more ice it takes to create interior leaking see ice dam case study 09.
A roof leak at the edge of a dormer can allow a lot of water to enter your home.
Dormer leaks can be caused from a number of issues.