How to Winterize & Prevent Frozen Pipes

What is plumbing winterization and why is it important?

Winterizing pipes involves a series of steps that prepare a home’s interior and exterior plumbing to withstand blistering cold temperatures without freezing – protecting against devastating pipe bursts and leaks. As water freezes and becomes ice, it expands. The expansion quickly builds pressure within pipes, which can lead to the type of pipe damage noted above.

Winterization is critical if you’re going to be away from your home for an extended period of time, like snowbirds who leave their primary residence during the winter and escape to a beachy vacation home. A key component of properly winterizing a vacant home is preventing any water from running through the pipes. The less water that exists within a pipe means the less likely it is to freeze and cause severe damage to your plumbing.

We’ve created a couple of checklists to put your mind at ease and help assist you with the winterization process for your vacant home, ensuring you don’t have to deal with any unpleasant surprises upon your return. As always, your local plumber is your best source for accessing and diagnosing your situation.  

Interior Plumbing Checklist:
  • Drain potable water system. Shut off main water valve. The main water valve will be located where the water supply enters the home, usually in a basement, crawl space or mechanical room. Valve handles will be handwheel or lever style. After shutting off the main water supply valve, open all faucets within the home and drain the system from a faucet at the lowest location in the home or closest to the main shutoff valve. In multilevel dwellings, draining the system from the lowest level will allow gravity to do the job of draining the system. In single level dwellings, draining the system as close as possible to the main water shut off valve will prevent water from being trapped in the system. Shutting off the main water supply and draining the water distribution system will decrease the probability of water freezing, which causes pipes to burst. 
  • Adjust water heater settings. Water heaters should be kept on their lowest setting. If you have a water heater equipped with a newer thermostat, we suggest setting it to ‘vacation mode’ to prevent water in the tank from freezing. Another plus? You won’t have to relight the pilot upon your return. 
  • Flush toilets. After turning of the water and draining the system, flush all toilets to remove excess water from the tanks. Pour an environmentally safe antifreeze into the bowl and the tank. The antifreeze will keep the flapper/seals in the toilet tank lubricated and prevent them from dry rotting.
  • Prep drains. Antifreeze should also be poured into all shower, tub, floor and sink drains (any fixture with a trap). This will ensure the water in the traps will not freeze but also prevent evaporation and maintain the traps' seal. Maintaining the trap seal will keep sewer gases and insects from entering the home.   
  • Do not turn off the heat. Set thermostat to at least 55 degrees Fahrenheit to prevent pipes from freeze damage. It’s always a good idea to have your heating system inspected/serviced to ensure reliability and performance – when you need them most.
  • Open cabinet doors beneath bathroom and kitchen sinks. This allows warm air to reach pipes.
  • Cover exposed piping with insulating sleeves or wrap. The method provides additional protection for your pipes against frigid temperatures, especially those located in uninsulated areas and along exterior walls.
  • Keep garage door shut. A closed garage door prevents cold drafts from making their way to plumbing on adjacent walls. You can also add weather-stripping, typically a strip of vinyl or rubber material that creates an airtight seal along your garage door (on the bottom of the door seal, stop molding, panels, top and sides of the door). Additionally, the draft-proof product traps heat and stops it from escaping the garage.   
Exterior Plumbing Checklist:
  • Shut off valves to external water supply. These are isolation valves located on the water lines leading to the external water supply (usually in a basement, crawl space or mechanical room). Once you’ve completed this step, open all taps until water is completely drained from outside hose bibbs. 
  • Disconnect garden hoses and fittings from hose bibbs. Any water left in attached garden hoses will freeze when the temperature drops. Water expands when it freezes and will take up more space than liquid water within the pipe. A water pipe can’t typically handle this type of expansion and will likely become damaged, such as suffering from a burst or broken valve.
  • Clean out gutters and downspouts. By doing so, you’ll remove any leaves and debris that could prevent proper water flow and cause ice build-up, which can lead to costly repairs.
  • Seal cracks. Check for any visible gaps or holes in siding, door frames or windows. Fill in both exterior and interior cracks with a sealant to block out nasty drafts that can freeze your pipes and increase utility bills.

Related Resources

Looking For More Resources?