Fan In Attic Ice Dam

Guide to detecting and correcting attic condensation and preventing ice dam leaks in buildings can reduce the chances or correct the causes of mold in attics.

Fan in attic ice dam.

But codes don t address all the issues and many houses are built without following building codes. An ice dam forms when the roof over the attic gets warm enough to melt the underside of the layer of snow on the roof. Condensation snow on roof and ice dam prevention tips building codes have some requirements that attempt to prevent the problems of ice dams and attic condensation. Ice dams on roofs attic moisture attic mold.

Not to mention soggy insulation in the attic which loses r value and becomes a magnet for mold and mildew. Posted november 18 2019 by lewis insulation filed under attic ventilation. There it freezes creating a rim of ice. This rim can grow trap more water behind it and bingo you have a full fledged ice dam.

Here in minnesota we get quite the snow filled winter. By circulating cool outside air in the attic space or in the rafter spaces just below the roof deck the roof surface remains below freezing and cannot melt the snow on the roof. The water trickles down between the layer of snow and the shingles until it reaches the eave of the roof which stays cold because it extends beyond the side of the house. Ask this old house general contractor tom silva explains the best ways to keep your roof and gutters free from those dreaded ice dams.

If you re wondering how to fix an ice dam on your roof here s how you can prevent them altogether or remove them if they ve already formed. When the meltwater runs down the roof it hits the cold edge not warmed by the attic. Houses with good attic ventilation generally do not experience ice dams and the physics are quite simple. And with our unpredictable weather and temperatures we are at a high risk of getting ice dams.

In addition seal all the places that warm air can escape into the attic like areas with wires and plumbing lighting fixtures heating fixtures chimneys etc. That s why attic fans are a non starter for ice dam prevention. See below for a shopp. And if the building uses a whole house ventilating fan especially if there is inadequate exit venting for the fan operation.

Only running the fan in the summer extended its life and it will cause more harm even to the fan motor itself in the colder months and it does not allow the fan to reduce moisture build up in the attic at all at these times and does not allow the fan to prevent ice dams during the winter. Simply insulating your attic will keep your home warmer and your attic cooler.