With the arrival of winter comes the potential for ruined carpets and water damage to your ceilings and walls caused by ice dams on roofs or bursting pipes. Fortunately, there are steps you can take to help prevent this kind of damage to your home. For structural changes, be sure to consult your local building officials, and hire a registered design professional, such as an architect, engineer or licensed building contractor to do the work.
Inside your home:
Frozen water in pipes can cause water pressure buildup between the ice blockage and the closed faucet at the end of the pipe. This causes pipes to burst at their weakest point. Pipes in attics, crawl spaces and outside walls are particularly vulnerable to freezing in extremely cold weather. Entry holes for television aerial leads, cable or telephone lines can allow cold air to reach them. Action to keep water in pipes from freezing would include:
Fitting exposed pipes with insulation sleeves or wrapping to slow the heat transfer. The more insulation, the better. Water pipes leading to the outside should be equipped with a hydrant-style faucet extending to the interior of the the house; alternatively, an inside shut-off valve should be fitted and closed in cold weather, with the exterior valve being left fully open.
Sealing cracks and holes in outside walls and foundations near water pipes with caulking.
Keeping cabinet doors open during cold spells to allow warm air to circulate around pipes (particularly in the kitchen and bathroom).
Keeping a slow trickle of water flowing through faucets connected to pipes that run through an unheated or unprotected space. Or drain the water system, especially if your house will be unoccupied during cold periods.
The home itself:
An ice dam is an accumulation of ice at the lower edge of a sloped roof, usually at the gutter. When interior heat melts the snow on the roof, the water runs down and refreezes at the roof’s edge, where temperatures are much cooler. Eventually, ice builds up and blocks water from draining off the roof. This, in turn, forces the water under the roof covering and into your attic or down the inside walls of your house. An ice dam can cause serious damage. Action now can avoid trouble later.
Keep the attic well ventilated. The colder the attic, the less melting and refreezing on the roof.
Keep the attic floor well insulated to minimize the amount of heat rising through the attic from within the house.
Consider installing electric heating cables on roof surfaces and in downspouts known to collect ice.
This three-step approach decreases the likelihood that ice dams will form or, at least, reduces their size. As an extra precaution against roof leaks (in case ice dams do form), install a water-repellent membrane under your roof covering. Talk with your local building official about minimum code requirements for ice dam protection. Unfortunately, ice dams may be unavoidable if your home has recessed lighting near the roof. Heat generated from these lights melts the snow, which then contributes to ice dam buildup. The only sure way to avoid this problem is to eliminate recessed light fixtures near the roof.
Outside your home:
The accumulation of ice and snow on trees and power lines can cause considerable damage. You can take action before a storm strikes to reduce the vulnerability of your home.
Remove weak branches and trees that could fall on your house.
The Institute for Catastrophic Loss Reduction
Toronto Office 20 Richmond Street East, Suite 210, Toronto, Ontario M5C 2R9 Tel: (416) 364-8677 Fax: (416) 364-5889
London Office Boundary Layer Wind Tunnel Laboratory University of Western Ontario 1151 Richmond Street, London, Canada N6A 5B9 Tel: (519) 661-3234 Fax: (519) 661-4273
