Ice Dams and Ice Buildup in the Attic
What is an ice dam?
Ice dams form due to melting snow that runs down the surface of the roof and then re-freezes as it reaches the edges of the roof. As more snow melts, the ice dam prevents water from properly draining off of the roof. Water will pool behind the dam and make its way under the shingles, re-freeze and lift the shingles from the roof, allowing water to enter the attic and home.
Ice dams can create significant damage, as water can leak into your home and damage insulation, ceilings and walls.
Ice dams can create significant damage, as water can leak into your home and damage insulation, ceilings and walls.
How to prevent ice dams:
The number one cause of ice dams on the roof is the lack of sufficient insulation and ventilation in the attic space. By adding more insulation and making sure there is enough ventilation in the attic, you can reduce the amount of heat that escapes from your home into the attic space, in turn reducing snow melt on the roof.
Installing a waterproof underlayment can prevent water intrusion and lower the risk of damage should an ice dam form.
Ice Buildup in the Attic
Ice buildup on roof sheeting in the attic occurs when water vapor builds up in the attic and freezes. As the outdoor temperature rises, ice will melt causing mold growth.
The causes of ice buildup are bathroom vents exhausting into the attic, holes around can lights and other openings in the ceiling, and lack of attic ventilation.
To prevent ice buildup on the roof sheeting:
make sure your bathroom vents are exhausting outside and not into the attic space,
caulk or patch any holes between living space and attic,
and add more roof vents.
The attic space temperature should be the same or close to the outdoor temperature.
Listen to our podcast