Ice dams begin to form when snow melts, runs down your roof, and refreezes at the edge. What causes the snow to melt is when the temperature of your roof reaches above 32 degrees. The roof edge however remains below freezing. Both of these factors working together are the cause of ice dams, a damaging, costly winter occurrence. When it comes to preventing ice dams, a good first line of defense is a cold roof. Here are 3 ways you can keep your roof cold to prevent the formation of ice dams:
Close Attic Bypasses
Much heat is lost by air leaking through many types of openings in your ceilings. To fix these leaks you will have to pull back the insulation in your attic and fill the open spaces using caulk, foam, or other methods. Be sure you are wearing a dust mask and a long sleeved shirt and pants to avoid skin irritation caused by fiberglass insulation.
Your Attic Insulation Level
It is important to make sure the depth of your attic insulation is adequate. If you find that you have less than 8 inches, especially if you have had ice dam problems in the past, you should add more.
Fiberglass and blown-in cellulose tend to leave fewer gaps versus hand-placed batts.It is also a good idea to hire a professional to do this for you.
Roof and Soffit Vents
Roof and soffit vents draw in the cold outdoor air and flush out the warm attic air with ventilation. Some roof types may be difficult to vent, for example homes with angled ceilings, or a roof with skylights. In this case you may have to rely on secondary strategies.
When it comes to assessing venting on homes that have had aluminum retrofitted over old soffits, things can get tricky. If you notice persistent ice damming in one area, it might be necessary to remove several aluminum sections to check the venting.
Keeping a cold roof will not only help prevent ice dams, but will also reduce heating and air conditioning costs. Ice dams are no walk in the park, costing you a lot of time, money, and energy. Get proactive and take steps now to prevent them from damaging your home!
Reference: https://www.familyhandyman.com/roof/prevent-ice-dams/view-all