Frost And Ice In Attic

Can sun get to the roof you will have either frost or water collecting.

Frost and ice in attic.

Frost itself doesn t do any damage but once it melts things get wet and then damage occurs. If this cycle repeats over several days the freezing snowmelt builds up and forms a dam of ice behind which water pools up into large puddles or ponds. Since our minnesota winters are usually dry the only other source of humid air is your living space. When it reaches the cold surface of the roof sheathing and framing it turns to frost.

Frost in your attic space is a sign that warm humid air is somehow getting into your attic space. When you see water and ice on the nails the actual temperature of the nails is at or below the dew point of the air in the attic that is saturated with water vapor. In the parlance of building scientists these cold wooden house parts make up a condensing surface much like a cold glass of ice tea beads with water on a hot summer day. When the moisture gets into the attic it condenses on the roof sheathing in the form of frost.

The water develops on the roofing nails first because they readily conduct cold. When warm air from inside the house escapes traveling up through the bypasses the moisture condenses on the roof boards and rafters where the frost can form. Ice dams are the large mass of ice that collects on the lower edge of the roof or in the gutters. Depending on the temperature and the insolation ie.

Frost and ice forms in attics when warm humid air accumulates and condenses on the underside of your roof sheathing. When moisture gets into the attic it condenses on the roof sheathing in the form of frost. When the temperature in your attic is above freezing snow on the roof will likely melt. During winter conditions attic frost is a problem associated with attic bypasses.

As more melting snow or rain runs down the roof it meets this mass of ice and backs up sometimes under the shingles and into the attic or the house. Water vapor is migrating upward and eventually filtering into the attic. The frost itself doesn t do any damage but once it melts things get wet which is when the damage. Ice damming usually occurs with a significant depth of snow on the roof.