Frost In The Attic Information

Lack of attic air sealing also allows frost to form as warm air penetrating into the attic causes moisture to condense on chilly surfaces.

Frost in the attic information.

Frost shows up in the attic when moisture laden air from the house gets into the attic. I noticed that i have frost in my attic in the winter and that one of my 2 roof vents is forming condensation which is dripping onto the insulation. To start frost accumulates when moisture laden air from the house gets into the attic. When the outside temperature rises again the frost thaws water collects and can leak into.

That s about it pretty simple. Frost gets into the attic from air leaks or attic bypasses. When the moisture gets into the attic it condenses on the roof sheathing in the form of frost. 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.

I ve blogged about attic air leaks many times and i ve shared photos of attic air leaks. I have a 1000sqft attic floor area with two 301 maximum static roof vents. When moisture gets into the attic it condenses on the roof sheathing in the form of frost. Full home humidity systems.

During winter conditions attic frost is a problem associated with attic bypasses. Inadequate attic air sealing. Cold weather climate winter lows of 25c. Houses with full home humidity systems are at risk for attic frost if the home s level of humidity is excessive.

The fix for frost in the attic is sealing attic bypasses these are passageways from the conditioned household space to the attic. 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. The frost itself doesn t do. While bypasses are certainly the most common cause of frost there are other ways it can happen and these are much more.