How to Winterize Your Plumbing and Prevent Frozen Pipes

What is plumbing winterization, and why is it important?

Frozen Pipes

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

Winterization is critical if you're away from home for an extended period, 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 water from running through the pipes. The less water within a pipe, the less likely it is to freeze and cause severe damage to your plumbing.

How to winterize your plumbing system

To put your mind at ease, we have a few checklists to help with the winterization process before you leave your home vacant. Following these steps will ensure you won't have to deal with any unpleasant surprises upon your return. As always, a local plumber is your best source for accessing and diagnosing your situation.

Eight steps to winterizing interior plumbing:

Interior plumbing involves anything within the home. Taking care of your household plumbing can help protect you from having an emergency repair. Here are eight steps to preventing frozen pipes and keeping your interior plumbing working properly:

1.    First, you will want to shut off the main water valve. The main water valve is located where the water supply enters the home, usually in a basement, crawl space, or mechanical room. Look for handles that look like a handwheel or lever. After shutting off the main water supply valve, open all faucets within the home and drain the system.

Oatey Tip: In multilevel homes, drain the system from the lowest level and allow gravity to do the job. In single-level homes, drain from the tap closest to the main shutoff valve. To avoid water from becoming air locked and draining slowly, you can also open a fixture at the highest point in the home and then the lowest.

2.    Adjust your water heater settings. Water heaters should be kept on the lowest setting. Suppose you have a water heater equipped with a newer thermostat. In that case, 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.

3.    Make sure to flush your toilets. After turning off the water and draining the system, flush all toilets to remove excess water from the tanks.

Oatey Tip: Pour an environmentally safe antifreeze into your toilet bowl and tank. It will keep the flapper/seals in the toilet tank lubricated and prevent them from dry rotting.

4. Prep all your drains. Pour antifreeze into all shower, tub, floor, and sink drains — basically, any fixture with a trap. This will ensure water in the traps will not freeze while preventing evaporation and maintaining the trap seal.

5. Do not turn off the heat. Set the thermostat to at least 55° Fahrenheit to prevent pipes from freeze damage. Having your heating system inspected/serviced is always a good idea to ensure reliability and performance when needed.

6. Open cabinet doors beneath the bathroom and kitchen sinks. This allows warm air to reach pipes.

P Trap Under bathroom sink

7. Cover exposed piping with insulating sleeves or wrap. This protects your pipes against frigid temperatures, especially in uninsulated areas and along exterior walls.

Pipe Wrapped in Insulation

8. Keep your garage door shut. A closed garage door prevents cold drafts from making their way to plumbing on adjacent walls.

Oatey Tip: Add a vinyl or rubber strip to the bottom of the garage door to trap heat and stop it from escaping. This draft-proof product can also help prevent mold.

Four steps to winterize exterior plumbing:

Exterior openings in the home should be closed to prevent frigid outside air from contacting indoor pipes. Here are some preventative steps you can take to keep your external plumbing safe:

1.    Shut off valves to the external water supply. These are isolation valves 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 the outside hose bibbs.

2.    Disconnect garden hoses and fittings from the hose bibbs. Any water in the 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.

Oatey Tip: If the valve is damaged, we recommend using an air compressor to blow out any residual water in the exterior lines to prevent it from further damage.

3.    Clean out your gutters and downspouts. Doing so will remove any leaves and debris that could prevent proper water flow and cause ice build-up, which can lead to costly repairs.

4.    Seal any visible cracks or gaps. Check for holes in the siding, door frames, or windows. Fill in exterior and interior cracks with a sealant to block out nasty drafts that can freeze your pipes and increase utility bills.

Man using caulk sealant to winterize

Prevent pipes from freezing by preparing for winter conditions. Identify which pipes are most vulnerable to the cold temperatures –– like pipes located on the outside walls, uninsulated pipes, and pipes within unheated spaces, and start there.

If you do not have the necessary equipment or skill set to winterize your own plumbing, we recommend contacting a professional for help.

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