Why Do Pipes Burst in Cold Weather?

Water is unique because it expands when it freezes into ice. This expansion is powerful and creates significant pressure within a confined space like a pipe. The pipe itself cannot stretch to accommodate the growing ice. If the pressure builds enough, the metal or plastic will fail, resulting in a burst. The force can be strong enough to split even sturdy copper or PVC pipe materials. Understanding this basic physical process is key to taking preventative steps.

A burst pipe can release hundreds of gallons of water per hour. This water quickly soaks into drywall, insulation, and flooring, causing structural damage. It can also ruin personal belongings and create electrical hazards. Mold growth can begin within 24 to 48 hours in the damp materials left behind. The longer water sits, the more extensive and costly the repairs become. This rapid damage is why acting quickly to stop the water and start drying is so important.

• Water soaks into porous building materials.
• Drywall and insulation become saturated and lose strength.
• Wood flooring can warp, cup, or buckle.
• Electrical systems and appliances can be damaged.
• The wet environment is ideal for mold spores to grow.
• Standing water can weaken a home's foundation over time.

Prevention is the most effective strategy. Insulate pipes in attics and crawl spaces with foam sleeves. On very cold nights, let a trickle of water flow from faucets served by vulnerable pipes. Keep cabinet doors open to allow warm air to circulate. You should also drain and disconnect outdoor hoses before winter to prevent trapped water from freezing in the spigot.

• Insulate exposed pipes with foam or fiberglass sleeves.
• Seal cracks and openings in exterior walls.
• Let cold water drip from faucets during extreme cold.
• Keep your home's thermostat set to at least 55 degrees if away.
• Drain water from swimming pool and sprinkler supply lines.
• Know where your main water shutoff valve is located.