Frozen pipes are a nightmare, especially during unexpected cold conditions. When water freezes inside pipes, it expands, creating pressure that can lead to bursts and water damage. Understanding how frozen pipes burst and how to prevent a frozen and burst pipe disaster helps protect your home. This Old House plumbing and heating expert, Richard Trethewey, demonstrates the explosive power of freezing water in pipes.
The Science Behind Frozen Pipes
When water freezes, it expands by approximately 9% in volume. While this alone isn’t typically enough to burst a pipe, it sets off a chain reaction that can damage your home.
Pressure Buildup
When water freezes in a section of pipe, it creates a blockage. The unfrozen water between this ice blockage and a closed faucet becomes trapped. As more ice forms, it pushes against this trapped water, increasing the pressure within the pipe. This pressure can quickly reach an astounding 25,000 psi (pounds per square inch).
The Breaking Point
Most residential pipes are not designed to withstand extreme pressure. As pressure builds, it eventually exceeds the pipe’s structural capacity, causing it to split or burst. The burst often occurs at a weak point in the pipe, such as a joint or a previously stressed area.
Results of a Burst Pipe
When a frozen pipe bursts, the results can range from water damage to electrical hazards and long-term structural issues.
Immediate Water Damage
Once the pipe bursts and begins to thaw, water will gush out quickly. This can quickly flood rooms, damaging floors, walls, and personal belongings. Even a small split in a pipe under normal water pressure can release a significant amount of water in seconds.
Potential Electrical Hazards
Flooding from a burst pipe can cause electrical hazards if the water comes into contact with outlets, appliances, or exposed wiring. This requires immediate attention to prevent the risk of electrocution or electrical fires.
Long-term Structural Issues
If not addressed quickly, water from a burst pipe can seep into building materials, leading to long-term problems such as mold growth, wood rot, and structural weakening. These issues can be expensive to repair and pose health and safety risks to homeowners.
Preventing Frozen Pipes
Taking proactive measures to prevent pipes from freezing is much easier and less expensive than dealing with the aftermath of a burst pipe.
Insulate Vulnerable Pipes
One way to prevent pipes from freezing is to insulate them in unheated areas such as basements, attics, and exterior walls. You can do this by using foam pipe insulation sleeves, wrapping the pipes with heat tape or heating cables, and sealing gaps around pipes where they enter the house.
Maintain Adequate Home Heating
Keeping your home warm helps to prevent frozen pipes, especially during extreme cold conditions. Set your thermostat to no lower than 55 degrees Fahrenheit to prevent pipes freezing, even when away from home. Keep your interior doors open for better heat circulation, and open cabinet doors under sinks to let warm air reach the pipes.
Allow Faucets To Drip
On very cold nights, allowing faucets to drip can prevent pipes from freezing. This technique relieves pressure in the pipes and keeps water moving, making it less likely to freeze. Choose a faucet furthest from where the water enters your home, allowing both hot and cold taps to drip.
Identifying Frozen Pipes
Knowing the signs of a frozen pipe can help you address the issue before it leads to a burst.
Reduced Water Flow
If you turn on a faucet and only a trickle comes out, you may have a frozen pipe. This is often the first sign that homeowners notice.
Frost on Exposed Pipes
For visible pipes, such as those under sinks or in basements, frost may accumulate on the outside of the pipe.
Unusual Sounds
As water begins to freeze and expand in pipes, you might hear unusual sounds like bubbling, banging, or whistling when you turn on a faucet.
Thawing Frozen Pipes Safely
If you think you have a frozen pipe, you must thaw it carefully to prevent it from bursting. Feel along the pipe to find the coldest point and look for frost or bulging. Apply heat carefully using a hair dryer, heating pad, or towels soaked in hot water. Never use an open flame or electrical appliance in standing water.
Start from the faucet end and work towards the coldest section on the pipe. Keep the faucet open while you work to defrost the frozen pipe so water can flow and relieve pressure in your pipes.
Emergency Response to a Burst Pipe
If a pipe in your home bursts, quick action can help minimize damage. Everyone in your home should know the location of your main water shutoff valve and how to operate it.
Turn the valve clockwise to shut off the water. For lever-style valves, turn the handle perpendicular to the pipe. Once the water is shut off, contact a licensed plumber immediately for repairs. Take photos and videos of the damage for insurance purposes and list any damaged items with their approximate value.
Additional Tips for Preventing Frozen Pipes
You can take more preventative measures to avoid frozen pipes in your home. Insulating outdoor faucets and hoses, monitoring local weather, and conducting inspections will help your pipes remain in good condition.
Insulate Outdoor Faucets and Hoses
Outdoor faucets and hoses are vulnerable to freezing temperatures. Disconnect and drain any hoses before temperatures drop very low. Install an insulated cover on outdoor faucets and use frost-free hose bibs for extra protection, or consider installing a freezeproof faucet.
Monitor Weather Reports
To prevent frozen pipes, watch for changing weather conditions during cold seasons. One option is to install a smart thermostat with weather alert features that send notifications to your home. You should also keep an eye on local forecasts during winter months so you can adjust the temperature in your home as needed.
Conduct Regular Inspections
Regularly inspecting your plumbing system can help identify any issues before winter sets in. Check for cracks or leaks in pipes, make sure any insulation is intact and installed correctly, and inspect your basement and attic areas for any drafts that could affect your home’s heating.
Frozen pipes pose a risk to homes in cold climates, but damage can be minimized with proper prevention and quick action. Remember, a great way to avoid pipe bursts is to prevent them through inspections and insulation methods.
