The steeper your roof pitch the more ice it takes to create interior leaking see ice dam case study 09.
Roof leak after snow.
If you have a low slope roof area accumulations as little as 1 thick can cause problems.
Worn out flashing or missing sealant can also cause roof leaks around dormers.
When i checked the roof i saw all the snow had fallen off the two story roof and landed on the addition.
Most roofing materials are designed to work under the influence of gravity.
Rotten or missing trim or siding can allow water to leak behind flashing and into your roof.
In the photo you can still see signs of an ice dam.
This keeps the warm air in and the roof at a constant temperature thus eliminating melting snow and roof leaks from occurring.
In order to avoid melting snow and roof leaks you need to have very good insulation ventilation and an effective air barrier.
The roof leaked a few days after a foot of snow had fallen.
Heat leaking up from your home is melting the snowpack in the tight roof canyon.
This roof leaks during the snowy part of winter and during storms in the summer certainly due to poor flashing.
The soffit that meets the roof is one of the toughest areas to waterproof.
Protection for the perishable areas of your roof.
An ice dam occurs when snow melts and the water freezes when it hits the colder edges of your roof.
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.
It was warm enough for the snow to melt during the day but it would drop below freezeing at night.