We get a lot of desperate calls every winter regarding ice dams especially during cold winter days with plunging temperatures at night. Ice dams occur when there is a thick blanket of snow on the roof that acts as insulation and traps heat that is leaking into your attic from heated spaces below. This heat eventually starts to melt the bottom of the snow causing water to run down towards the edge of the roof where there is less heat loss causing the water to freeze into ice, especially during cold nights. As more and more water runs down the ice gets thicker creating a dam that causes water to back up behind the dam, under the shingles and into the house.
If ignored, damage from ice dams can include ruined attic insulation, rotted wood, water damage to ceilings, walls, windows, possible mold growth & more. So, what is the solution? It is important to look at a variety of things as none by themselves will completely eliminate ice dams:
Air leaks: Remember, heat loss into the attic is the enemy. Installing insulated exhaust fan ductwork or replacing recessed lights with recessed housings which are rated to be insulated can reduce heat loss.
Attic Ventilation: Increasing the amount of ventilation through soffits, gable & ridge vents and up through the peak of the roof lowers the attic temperature and reduces snow melting on the roof. Even simply adding more roof vents may help.
Eave waterproofing: If your roof is being replaced you should consider having a waterproof membrane installed under the shingles at the eaves and in the valleys.
Clean Gutters: Gutters packed with leaves can provide a shelf for ice and snow to build up. Make sure your gutters are cleaned before winter to help keep any melted snow flowing away from the roof.
– Heat Tape: When placed near the edge of the roof, in gutters & downspouts, or in roof valleys, heat tape may relieve ice buildup in problem areas.
– Remove snow build-up: Removing the snow at the edge of the roof with a roof rake may be helpful but this must be done as soon as the snow has accumulated and before ice dam has a chance to begin to form. Avoid using sharp items such as axes or picks on your roof. These are likely to cause shingle or structure damage. Clifton Park Contractor provides roof-raking services both “by appointment” and on an “on call” basis.
Sometimes, the design of your home cannot allow for complete elimination of ice dams, but addressing the above items can help. If you have had ice dams in the past you will have them again when conditions are right.
Don’t wait until your roof is covered with snow and ice.
Ice Dam Damage
If this situation continues, the ice can work its way back up the roof edge, get under shingles, melt and leak into the exterior wall, home or attic. Damage from ice dams may not be readily apparent. As the ice melts and possibly drips into the wall or attic, insulation can be become wet and lose its ability to perform. In some cases if the right temperature and humidity exist, mold may begin to grow in the attic. Often paint will peel or blister weeks or months after the ice dam has melted as moisture from the leak in the wall or ceiling cavities tries to leave and pushes outward. Call immediately before the problem gets worse.
Recommendations on how to beat ice dams in the winter:
- Act fast with a roof rake during a heavy snow: As I mentioned earlier, ice dams happen quickly after a heavy snow because of the insulating properties of snow. If you can get out and rake your roof with a special tool called a roof rake to remove at least the lower 4 feet of snow from the roof edge, you’ll do a lot to prevent the ice dams from even forming. A roof rake is like a shovel that is turned on its side so that you can pull snow off the roof toward you. It has a long handle about 16 to 21 feet long, and is safer than many other approaches since you use the tool from the ground, not on a ladder.
- Calcium chloride or ice melt product: If you have an ice dam forming, one action you can take is to put a calcium chloride or similar product on the ice. (Forget any urban legends you may have heard about putting salt in pantyhose, it does not work well, takes a lot more salt and results in the pantyhose ripping apart). When you put the calcium chloride directly on the ice, be careful if you are on a ladder, icy conditions and ladder usage are not recommended so please be careful.