How To Prevent Frozen Pipes
Frozen pipes burst because as water freezes, it expands. With enough expansion, pipes will develop cracks. The cracks may not be visible but they will leak nonetheless when the ice melts.
Caution: Please read our safety information before attempting any testing, maintenance or repairs. Some equipment may rely on a cold water supply. Take appropriate steps to shut down any equipment that may be adversely affected by shutting off the water supply. Such equipment includes, but is not limited to, a boiler or other heating system.
Tips to Keep Pipes from Freezing
Pipes in exterior walls, unheated portions of your home and outdoors are at risk of freezing. Buried pipes must be buried below the frost line to be safely insulated. The frost line varies by geographic location. Sprinkler systems should be drained to prevent freezing. Drain the sprinklers as the wet season begins.
Pipes in exterior walls are subject to the cold. While they may be somewhat insulated, they can still become cold enough to freeze. In some cases the pipes are located in the exterior wall because they serve a fixture that is placed against that wall. In the case of a sink, it may be helpful to open the cabinet doors under the sink to allow warm interior air to warm the wall and help protect the pipe. A portable heater can be placed a safe distance from the wall and combustible material as an aid to warm the pipes.
It may be possible to fill cavities in walls around pipes by poking a small hole through the interior wall and spraying expanding, insulating foam through the hole. The key problem is knowing whether you adequately surrounded the pipe and filled the void. Adding too little foam may leave you with the false impression that you have solved the problem. Calculate the approximate volume of space between the studs, purchase enough foam to fill the void and poke the hole slightly above the point you want to fill up to. Use caution to avoid over-filling the void. Expanding foam can bow or crack drywall.
If it is impossible to adequately warm the wall containing the water pipes, then leave a trickle of water running from the faucet. Open both the hot and cold water valves. Moving water freezes much more slowly that still water. Leave a trickle running from any faucet that tends to freeze up. Leaving water running from the far end of the house also helps to protect the main water line runs.
Exposed pipes in the attic, basement or crawl space can be wrapped with insulating material or electrical wire heating wrap designed to wrap around and warm pipes. Leaving a trickle of water running from faucets, especially at the far end of the house, as described above, is also helpful.