Turn off the water immediately at the main shut off valve. Open the faucet so that water will flow through the pipe once the area is melted. This will help melt more ice. Apply heat to or around the pipe using a hair dryer.
Ideally, to protect from freeze damage, the water supply should be shut off and the pipes should be purged (drained) of water.
When the weather is very cold outside, let the cold water drip from the faucet served by exposed pipes. Running water through the pipe - even at a trickle - helps prevent pipes from freezing.
Pipes typically burst when exposed to extremely low temperatures for an extended period of time (anywhere from 1-3 days depending on temperature). This is especially true for pipes located on exterior walls. A frozen pipe is likely to burst when any water or liquid trapped within it freezes and begins to expand.
Water pipes burst because the water inside them expands as it gets close to freezing, and this causes an increase in pressure inside the pipe. When the pressure gets too high for the pipe to contain, it ruptures. This expansion phenomenon seems natural, but interestingly, it is a chemical anomaly.
A common misconception is that the drip prevents water from freezing because it stays in motion when it's running through the pipes. Although this helps, the truth is that at extreme temperatures water can freeze even while it is flowing.
Overall, it's best that you take heed and drip your faucets when temperatures dip below freezing. A simple trickle of hot and/or cold water—both from faucets inside and outside the home—can prevent you from having to deal with a much larger issue (and bill!) in the long run.
Your pipes will eventually begin to thaw on their own once the temperatures rise above freezing. As they do so, you may begin to hear your pipes making gurgling, clanging, or banging sounds as the ice begins to move. The hot water heater may do the same.
If your pipes have been frozen for more than two days, shut down your home's water supply. Locate the frozen length using touch, sight and sound. Make sure the pipe hasn't burst, and open indoor faucets. Unfreeze the pipe using a hair dryer, heat tape, space heater or heating pad.
It's important to note that you shouldn't fully open your faucets and plumbing fixtures directly after a freeze. This will drastically increase the water pressure within the pipes if there is any frozen water inside them, causing the pipes to burst.
Be prepared to wait at least 30 to 60 minutes. When the pipe begins to thaw, water will start flowing at a faster rate through the open faucet. Even after the water pressure is fully restored, it's recommended to keep the heat on the pipe to ensure the ice in the line is completely melted.
DURING freezing weather:
Open cupboard doors under sinks, especially where plumbing is in an outside wall, to allow interior heat to warm the pipes. If you plan to be away from home for several days, shutting off the water can reduce the chances of broken pipes.
Yes, pipes can freeze overnight if temperatures plummet drastically. Uninsulated pipes in unheated areas like attics or exterior walls are most vulnerable.
Ask any plumber, "Should I turn off the water if pipes are frozen?" and they'll immediately tell you, "Yes." Locate your main water line and switch the shut-off valve so the flow of water stops. By doing this, you'll reduce the amount of pressure that builds inside your frozen pipes.
As temperatures continue to drop, so does the amount of time required for pipes to freeze completely and eventually burst. Depending on various factors, the water inside pipes can start freezing in just 6 hours, though it's more common to see damage and issues after one to three days of subfreezing temperatures.
Manually thaw: Begin the thawing process at the most vulnerable places (near faucets). By targeting these areas first, your pipes will be less likely to burst. To do so, gently apply heat to the frozen areas. A blow dryer is a good option (use caution, go slowly, and don't use an open flame).
The job goes more quickly by pouring hot water or a mixture of vinegar, baking soda and salt water down the drain. Space heaters, hair dryers and heating pads are highly efficient tools for unfreezing a drain pipe. If a frozen drain line ruptures, turn off your home's main water supply.
Pipes: Turn off water supply to the house and drain pipes to protect them from freezing. You can empty pipes by running the water and flushing the toilets after the water has been turned off. After draining the pipes, it is a good idea to leave the faucets open to prevent pressure build up from any water that remains.
Turn on all faucets: Checking each faucet in your home will help you narrow down your search. The faucets that have little or no water pressure likely have a frozen pipe in their supply line. If every faucet is showing low water pressure, the frozen pipe may be near the water meter.
Small amounts of trapped water can quickly turn into ice when temperatures drop. As water freezes and expands, it can still cause the pipes to burst if you don't drain them properly. This expansion can create significant pressure within the pipe walls, leading to cracks or complete bursts.
In general, you should let at least one faucet drip in each section of your home. This is particularly crucial if your home has multiple floors or distinct areas, like an extension or a wing. If you have the option, choose faucets that allow you to control hot and cold water separately and let both drip slightly.