The short answer
The Science of Freezing Water
Water expands by about nine percent in volume when it turns to ice. This expansion occurs inside a confined pipe, where the water has nowhere to go. The resulting internal pressure builds until it finds the weakest point in the pipe wall. That pressure is often strong enough to split metal or plastic pipes, leading to a burst when the ice thaws or immediately under the strain.
Common Locations for Vulnerable Pipes
Not all pipes face the same risk. Those most likely to freeze are in unheated interior spaces like attics and garages. Pipes running through exterior walls or under cabinets on outside walls are also highly susceptible. In many regions, these risks are often overlooked until a rare cold snap occurs.
- Pipes in unheated crawl spaces or utility rooms.
- Supply lines for outdoor hose bibs or sprinkler systems.
- Water lines in attics or garages without insulation.
- Pipes inside kitchen or bathroom cabinets on north-facing walls.
- Swimming pool supply lines that were not properly drained.
- Any plumbing in a second home or vacation property that is not heated during cold weather.
How a Small Crack Creates Major Damage
A burst pipe does not always mean a dramatic explosion. Often, it starts as a small crack or pinhole leak. When the ice inside the pipe finally melts, water flows out through this opening under the full pressure of your home's water supply. This steady stream can release hundreds of gallons per hour, quickly flooding floors, walls, and personal belongings. The water can seep into wall cavities and subflooring, causing structural damage and creating conditions for mold growth within days.
Preventive Steps Homeowners Can Take
You can take several actions to protect your plumbing. Before cold weather, drain water from outdoor lines and disconnect garden hoses. Indoors, keep cabinet doors open to allow warm air to circulate around pipes. Let a faucet drip slowly during a hard freeze, as moving water is harder to freeze. Insulate pipes in attics and garages with foam sleeves for added protection. For pipes in particularly cold spots, you can apply thermostatically controlled heat tape, following the manufacturer's instructions carefully.
What to Do If a Pipe Bursts
Your first action must be to stop the water flow. Locate your home's main water shutoff valve and turn it off immediately. It is wise to know your shutoff valve location before an emergency. Then, call local water damage pros to address the flooding. Move what items you can to a dry area and take pictures for a potential insurance claim. Policies vary, and your insurer decides what is covered. While waiting for help, you can use towels to contain small puddles, but do not attempt electrical repairs in wet areas.
Water damage does not wait
Phones are answered 24/7 for Chandler and nearby communities.
Call Now (480) 526-4676Frequently asked questions
At what temperature do pipes typically freeze?
Pipes are at risk of freezing when temperatures stay at 20 degrees Fahrenheit or below for an extended period. However, uninsulated pipes in exterior walls can freeze if outside temperatures hit the mid-20s, especially with a strong wind chill reducing the temperature of the wall cavity.
Can pipes burst even if they are not frozen?
Yes, though it is less common. Corrosion, high water pressure, physical damage from construction, or a pre-existing weakness can cause a pipe to fail. A sudden pressure surge in the system, known as a water hammer, can also rupture an already compromised pipe.
Who should I call for burst pipe cleanup?
You should contact local water damage pros for cleanup and drying. They have the equipment to extract water, dry structures, and help prevent mold. For the actual pipe repair, you will need a plumber to fix or replace the broken section.
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