How Cold Roofs Prevent Ice dams

Posted by roofcoadmin April 9, 2019

The glistening icicles dangling from the eaves may be among the beauties of winter, but they also spell trouble. Icicles are a sign of ice damming; a condition that occurs when snow melts on a warm area of the roof then flows downslope until it refreezes on a colder area, usually near the eaves. Subsequently, meltwater then pools above the icy obstruction and does its dirty work.

A combination of poor roof ventilation and warm attic space is what causes formation of ice dams. Clogged or poorly draining gutter systems exacerbates the problem. When you ignore an ice dam, you risk loosening your roof’s shingles, tearing off gutters and causing roof leaks. The results of this are stained and sagged ceilings, peeling paints, and of course a humid attic which is a magnet for mold.  Preventing ice dams simply requires you to keep your attic and roof cold. How do you do this? Read on…

Stop air leakage by closing up attic bypasses

Naturally, warm air rises and continuously moves up the bypasses escaping into the attic. Gaps in the drywall, access hatches, plumbing pipes, chimneys, cracks around light fixtures, and other ceiling penetrations will all cause air leaks. In addition to being the primary source of ice dams and attic frost, bypasses also cause indoor moisture problems. To close up the bypasses, invite a roofer to conduct to ascertain the exact source of the leaks then seal them.

Adding roof and soffit vents will increase attic ventilation

An important part of a healthy roofing system is roof vents. Roof vents allow proper attic ventilation, prevent early aging of the roofing materials, and also prevent condensation. To effectively cool the attic, you can take advantage of the natural circulation by bringing in fresh air into the attic through soffit vents right under the eaves. This then expels hot air through the gable vents that near the peak of the roof. Proper attic ventilation also moderates temperature in the rest of the home. Ideally, half the vents should be installed in the soffit at the bottom of the roof and half near the top to allow for natural circulation of air through the attic. Multiplying the length of the attic with the width in feet to find the attic area, then dividing by 150 to find the total square feet of vent space needed, will help you calculate the total vents needed.

Your attic insulation level matters

Building experts recommend about 12 to 14 inches of cellulose or fiberglass insulation. If you have less than inches, you are likely to experience ice dam problems. Fiberglass and blow-in cellulose are always a better option compared to hand-placed batts. This is because they leave fewer gaps by filling more tightly around the joists, rafters and other obstructions.  Maintaining sufficient levels of insulation helps prevent ice dams.

Heat loss from the house, cold temperatures, and a thick snow layer are the three things ice dam needs in order to develop. Obviously, you can’t control the outside temperatures but you can control heat loss by improving ventilation and insulation as highlighted in this article. To prevent snow from building up on the roof (which is the other cause of ice dams), inviting Winnipeg snow removal professionals will help you deal with the problem early on.