How a freeze-and-thaw leak unfolds
- During a cold snap
- Overnight lows drop well below zero. Pipes in unheated garages, crawlspaces, cantilevered floors and outside walls lose heat fastest.
- While frozen
- Ice expands and pressure builds between the ice plug and a closed faucet. The pipe splits or a fitting separates, but the ice still seals the gap.
- When it warms
- The ice melts and full water pressure pushes through the split. Water runs until someone notices or shuts the main.
- Hours later
- Water shows up on a ceiling below a bathroom, along a baseboard on an outside wall, or across the garage floor and into the house.
Where Aurora homes are most exposed
Arctic air reaches the Denver area several times in most winters, and temperatures can fall hard in a few hours. Every era of house has weak spots. An older ranch may have pipes in an outside wall under the kitchen window, or a hose bib without a frost-free valve. A newer two-story often puts a bathroom over the garage, with supply lines in a floor next to unheated space. Townhomes and condos may run lines through exterior soffits or beside a shared garage.
For water removal, the trouble is that water from a split pipe inside a wall or ceiling doesn't show up where it starts. It runs down the cavity, soaks insulation and the back of the drywall, and spreads along the bottom plate. Extracting the water you can see on the floor is half the job. Someone has to open the cavity or dry it in a controlled way, and the insulation in an exterior wall is often soaked.
Right after you find the leak
- Close the main shutoff and open a faucet at the lowest point to bleed off pressure
- Turn off power to any circuit where water is running near fixtures or outlets
- Leave cabinet doors open and warm the area gradually. Never thaw pipes with an open flame
- Have a plumber repair the break before the water goes back on
- Photograph the wet ceiling, wall and floor, and the split pipe once it's exposed
- Notify your insurer. Frozen-pipe damage is often covered when the home was kept heated, so note the thermostat setting
Common questions
Should faucets drip during a cold snap?
Letting a faucet on an exposed line drip a little can lower the chance of a freeze. Opening sink cabinets on outside walls so room heat reaches the pipes also helps.
Does disconnecting garden hoses matter?
Yes. A hose left attached can trap water in a frost-free hose bib, which defeats the design and lets it freeze and split inside the wall.
General information for Aurora, not a quote or professional advice. In an emergency, call 911.