The short answer
The Freezing Point
Water freezes at 32 degrees Fahrenheit, but pipes usually do not freeze the moment the air hits that mark. The water inside a pipe needs time to lose enough heat to reach the freezing point. If the air stays at 32 degrees for several hours, the risk climbs, especially for pipes in unheated spaces like attics, garages, or crawlspaces.
A more practical threshold is 20 degrees Fahrenheit. At that temperature, exposed pipes can freeze within a few hours. Pipes inside walls or under insulation take longer, but they can still freeze if the cold lingers. The exact temperature that causes trouble depends on your home's layout and how well the pipes are protected.
Why Pipes Burst
When water freezes, it expands by about 9 percent. That expansion pushes against the pipe walls, creating pressure. If the pressure builds too high, the pipe cracks or splits. The break often happens at a joint or a weak spot, and the damage may not be visible until the ice thaws and water starts flowing again.
A burst pipe can release gallons of water per minute, soaking walls, floors, and belongings. The longer the leak runs, the more extensive the water damage becomes. Acting quickly to shut off the main water valve and call for help can limit the mess. Even a small crack can cause major issues if left unchecked.
- Keep garage doors closed to shield exposed pipes
- Open cabinet doors under sinks to let warm air circulate
- Let a slow drip from faucets to relieve pressure
- Wrap pipes in insulation or heat tape
- Set the thermostat to at least 55 degrees when away
- Know where your main shutoff valve is located
Signs of a Frozen Pipe
A frozen pipe often gives off clues before it bursts. You might notice a lack of water from a faucet, a gurgling sound in the lines, or a visible frost layer on the pipe surface. If you suspect a freeze, check the pipe for ice buildup and feel for cold spots along its length.
Never use an open flame to thaw a pipe, as that can cause a fire or steam explosion. Instead, use a hair dryer, space heater, or warm towels. If the pipe has already burst, turn off the water supply immediately and call local water damage pros to handle the cleanup.
What to Do After a Burst
If a pipe bursts, your first step is to shut off the main water valve to stop the flow. Then, turn off the electricity in affected areas if water has reached outlets or appliances. Move valuables and furniture away from the leak to reduce damage. Document the scene with photos for your insurance claim, if you plan to file one.
After the water is off, contact a plumber to repair the pipe and local water damage pros to dry out the area. Water can seep into drywall, flooring, and insulation, leading to mold if not handled quickly. The pros will assess the extent of the damage and begin the drying process. Policies vary, and your insurer decides what is covered.
Prevention Tips for Warm Climates
Even in warmer regions, freezing can happen during a rare cold snap. If you live in St. Petersburg, you might not think about frozen pipes often, but a sudden freeze can catch you off guard. Prepare ahead by insulating exposed pipes in your garage, attic, or under the house.
During a freeze warning, keep your heat on and open cabinet doors to warm the pipes. If you leave home, set the thermostat to at least 55 degrees. Knowing where your shutoff valve is can save you from a flood. A little planning goes a long way in avoiding a costly mess.
- Insulate pipes in unheated areas
- Drain outdoor hoses and shut off exterior valves
- Seal gaps around pipes where cold air enters
- Keep a slow drip on faucets during extreme cold
- Check your home's insulation for weak spots
Need help right now?
Call (727) 308-5518 any time, day or night, and describe what happened.
Call Now (727) 308-5518Frequently asked questions
How long does it take for pipes to freeze?
It depends on the temperature and pipe exposure. At 20 degrees Fahrenheit, exposed pipes can freeze in about two to four hours. Insulated or interior pipes may take longer, sometimes up to a day. The colder the air and the longer the exposure, the higher the risk.
Should I let my faucets drip to prevent freezing?
Yes, letting a faucet drip can help. A slow trickle keeps water moving, which makes it harder for ice to form. The drip also relieves pressure in the system if a pipe does freeze. Run the drip from the faucet farthest from the main valve to keep water flowing through the whole system.
What should I do if I suspect a frozen pipe?
Turn on the faucet to see if water flows. If not, check for frost on the pipe. Thaw it gently with a hair dryer or warm towels, starting from the faucet end. Never use an open flame. If the pipe is cracked, shut off the main valve and call a plumber.