When moisture gets into the attic it condenses on the roof sheathing in the form of frost.
Frost in attic space.
Bypasses are what allow moisture in the attic to begin with and this is what needs repair.
Frost itself doesn t do any damage but once it melts things get wet and then damage occurs.
Melting frost can lead to the deteriorated roof sheathing mold on the roof sheathing wet insulation and water stains on the ceilings.
When the moisture gets into the attic it condenses on the roof sheathing in the form of frost.
While bypasses are certainly the most common cause of frost there are other ways it can happen and these are much more obvious.
Can sun get to the roof you will have either frost or water collecting.
Frost in your attic space is a sign that warm humid air is somehow getting into your attic space.
When the outside temperature rises again the frost thaws water collects and can leak into your house.
How does humid air get from our house and into the attic.
Depending on the temperature and the insolation ie.
The frost itself doesn t do any damage but once it melts things get wet which is when the damage.
The fix for frost in the attic is sealing attic bypasses these are passageways from the conditioned household space to the attic.
Since our minnesota winters are usually dry the only other source of humid air is your living space.
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.