Frost In Attic Melting

This post is largely a re blog of my last post on attic frost but that was from 2013 and it s time for a reminder about all of this.

Frost in attic melting.

During winter conditions attic frost is a problem associated with attic bypasses. House pressure affects. If you ve ever experienced a leaky roof when it s not raining this is often the symptom of frost melting in the attic and this should be investigated before worrying about getting on the roof to examine seals and shingles. While crawling in attics i often see a few drips here or there in the insulation where you can see evidence of minor frost melt.

When a warm sunny day arrives after a long cold stretch and it seems like you have a roof leak when there isn t a cloud in the sky it s probably attic icing otherwise known as ice dams or ice damming and the surprising thing is that it s very unlikely that the roof covering itself is the problem. When the outside temperature rises again the frost thaws water collects and can leak into your house. When moisture gets into the attic it condenses on the roof sheathing in the form of frost. Then the air condensates on the wood of the interior of your roof which is the coldest part of the attic.

The humid air in your home rises to the top of your home the attic when the temperature gets too low. Received 33 votes on 30 posts. How to prevent frost in the attic frost comes from air leaks. The more humid a house is the more frost you ll find in the attic.

It s rarely enough to cause a problem because the insulation sucks it up small quantities of water like a dry sponge. More indoor humidity more frost in the attic. I ve blogged about attic air. If the ventilation is working and the source of moisture has been eliminated the current frost and moisture will evaporate hopefully before it melts and drips.

Melting frost can lead to deteriorated roof sheathing. 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. Melting frost can lead to deteriorated roof sheathing mold on the roof sheathing wet insulation and water stains on the ceilings. Frost and ice can go straight from a solid state to a vapor and cold outside air is frequently very dry.

Frost gets into the attic from air leaks or attic bypasses.