When temperatures fall below 32 degrees Fahrenheit, it is considered freezing. Typically, short periods of freezing temperatures do not result in damage to pipes or facilities. However, when temperatures fall below 30 degrees Fahrenheit for more than eight hours, it is classified as a hard freeze.
Your pipes are at risk of freezing any time temperatures drop below 32°F. However, it's much more common for pipes to freeze when temperatures dip below 20°F. The longer the weather remains below freezing, the more likely it is your pipes can freeze if not properly protected and winterized.
Hard freeze typically occurs when the temperature reaches 28°-or-lower for at least an hour (or more). This usually means that most seasonal vegetation will be destroyed. In addition, there is a possibility of damage to unprotected outdoor plumbing/un-drained sprinkler systems etc.
We all know that freezing begins at 32° F or 0° C, but at what point do pipes freeze within our own homes? Temperatures only need to drop to about 20° F for a few hours to put exposed pipes at risk. So, your best bet is to insulate your exposed pipes to keep that temperature well above the freezing point.
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.
Yes, pipes can freeze overnight if temperatures plummet drastically. Uninsulated pipes in unheated areas like attics or exterior walls are most vulnerable.
Frozen pipes will eventually thaw on their own, but it could take days or even weeks. If New York City is experiencing a brutal cold snap, the temperature could stay below freezing for many days. Meanwhile, the water in the pipes could be expanding.
Prevent Frozen Pipes
Moving water keeps pipes from freezing. Find shut off valves for emergencies. Insulate pipes in unheated areas. Open cupboards and vanities to warm pipes.
Keep the Heat On
The ideal temperature would be around 55 to 60 degrees. This will be warm enough to keep pipes from freezing.
Be careful not to make extreme changes to your home temperature. An indoor temperature of less than 55 degrees may lead to freezing pipes, while anything more than 80 may damage drywall.
A hard freeze is anything within the range of 28 - 25 degrees.
But to be considered a “hard” freeze, temperatures must drop to at least 28 degrees and stay there for a significant amount of time, usually at least a few hours.
The 25th and 75th percentiles are 11 October and 28 October, meaning that the first freeze occurs between these two dates 50% of the years. For the purposes of this article, a hard freeze is defined as 26 ̊ F. On average, the first hard freeze is about two weeks after the first light freeze.
A toilet won't flush with frozen pipes. You can clear it once using water already stored in the tank, but you have to pour water in the bowl to flush again until you can thaw the toilet pipes.
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.
Frost becomes more widespread when the temperature falls below 32°F with some freeze possible. A hard freeze is possible when temperatures fall below 28°F.
What Temperature Will Cause My Pipes to Freeze? Pipes run the risk of freezing at temperatures below 32 degrees Fahrenheit, especially if they're not insulated, but most insulated pipes start to freeze at 20 degrees Fahrenheit or below.
As a general rule, the “temperature alert threshold” for freezing pipes is about 20 degrees Fahrenheit.
Frozen pipes generally occur below 20° F. But freezing can happen above that threshold as well, especially if you have uninsulated pipes running through an uninsulated space. Keep garage doors closed, especially if there are water supply lines in the garage.
Although common, frozen pipes do not always burst. However, the ice can increase this risk when it thaws and is usually worsened as it raises pressure further which makes pipe bursting common near winter's end or springtime. Furthermore, the more water flowing through the pipe, the greater chance of rupture.
Immediately after you turn off the main water valve, turn on a tub or sink faucet to its highest level, for both hot and cold connections. This relieves the pressure in the plumbing lines, and also ensures a full shut-down. Continue to open faucets around the house to drain down the home.
In general, you should let at least one faucet drip in each section of your home.
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.
Thawing Frozen Pipes
While you wait, reduce water pressure by opening all the faucets inside the home one-quarter turn. Water will begin to trickle out, helping the ice to thaw. Remember to close all faucets after full water pressure is restored.
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).