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.
Ice dam no attic.
This scenario is often the result of a warm attic.
If you have a furnace in the.
Houses with good attic ventilation generally do not experience ice dams and the physics are quite simple.
Ask this old house general contractor tom silva explains the best ways to keep your roof and gutters free from those dreaded ice dams.
In the tutorial it also describes some of the preventative things you can do before winter including.
The good news is there are several ways you can prevent ice dams if you ve got a cathedral ceiling.
This only occurs when part of your roof warms to above 32 degrees f warm enough to melt the snow while the roof edge remains below freezing.
That s why attic fans are a non starter for ice dam prevention.
Ventilation during the winter helps to reduce moisture as well as keeps attics dry and at an even temperature.
The dam grows as it is fed by the melting snow above it but it will limit itself to the portions of the roof that average below 32f.
This water finds cracks and openings in the exterior roof covering and flows into the attic space.
Proper attic ventilation can prevent ice dams.
Ice dams and icicles form when the snow melts runs down your roof and refreezes near the edge.
Although excess heat moving from the attic through the roof rapidly melts snow once the meltwater touches the cold eaves it quickly freezes and forms an ice dam.
Simply insulating your attic will keep your home warmer and your attic cooler.
The bad news is you ll need a good contractor to help execute them.
The cause of ice dams on the roof can be explained in two words excessive attic heat.
There are several means of improving attic ventilation.
Excessive attic heat causes some areas of the roof to be warmer than others.
To protect against damage to your structure and to reduce energy usage.
So the water above backs up behind the ice dam and remains a liquid.
See below for a shopp.
Ice dams can be a real problem in winter.
The result is that the snow on the roof melts unevenly usually leaving huge chunks of ice intact along the roof edge but with melted snow behind.
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.
Have a contractor create an air barrier.
