Winterizing a Puget Sound Home

Winterizing a Puget Sound home is a short list, not a weekend-long project, because our winters are mild most of the time. The list matters anyway, because every few years an arctic front drops us into the teens and finds every weak point at once. Disconnect the hoses and protect the bibs, insulate the crawlspace pipes, set the heat pump up for cold weather, keep fresh air moving through a sealed-up house, and know the cold snap playbook before you need it. Here is each step in detail.

Why winterize a home in a mild climate?

Because Puget Sound homes are built for the average winter, not the exceptional one. Average January nights sit in the mid 30s, so builders here ran water lines through vented crawlspaces and exterior walls, skipped insulation that colder climates require, and nobody noticed for decades. Then comes a week like late December 2022, when the region sat in the teens for days, and plumbers spent the following month repairing burst pipes across every neighborhood from Tacoma to Arlington.

The good news: the gap between a vulnerable house and a protected one is a few hours of work and modest materials. You are not preparing for a Minnesota winter. You are preparing for the five to ten hard-freeze nights that show up in a typical year and the occasional arctic outbreak that shows up in a bad one.

What should you do with hose bibs and outdoor faucets?

Start here, because it is the most common freeze failure we see and the cheapest to prevent. A garden hose left attached traps water inside the faucet and the pipe behind it. That water freezes, expands, and splits the pipe inside your wall, where you will not discover it until the thaw, or until the wall gets wet.

• Disconnect every hose by late October. Drain them and store them.
• If your home has interior shutoff valves for the exterior faucets, close them and open the outside bib to drain the line.
• Add insulated faucet covers. They cost little and take seconds to install.
• If a bib drips or will not shut off fully, have it repaired before the freeze, since a slow leak feeds ice.

Frost-free hose bibs are a worthwhile upgrade on older homes, but only if the hose is disconnected. With a hose attached, even a frost-free bib will freeze.

How do you protect pipes in the crawlspace?

Most homes here sit over a vented crawlspace, and that is where the water lines run, exposed to whatever the outside air does. Put on old clothes, take a flashlight, and go look. Any bare copper or PEX you can see should get foam pipe insulation, which slides on in minutes. Pay special attention to lines near the vents, where freezing air blows directly across them, and to the main supply line entering the house.

Crawlspace vents are part of the system: open in the wet months for moisture control, closed or covered during a hard freeze to keep the coldest air away from the pipes. Reusable vent covers make this a five-minute job each time. This overlaps with freeze protection enough that we wrote a separate deep dive on preventing frozen pipes, which covers heat tape, drip strategy, and what to do if a line freezes anyway. If you find a pipe that has already cracked or a fitting weeping under the house, our pipe repair team can fix it before winter turns a weep into a flood.

What are the right heat pump settings for winter?

Heat pumps have become the default heating choice around Seattle, and they handle our winters well when set up correctly. A few rules make the difference.

• Set it and leave it. Heat pumps work best holding a steady temperature. Big nightly setbacks force long recovery runs, often on expensive backup heat, and can cost more than they save. Small setbacks of a degree or two are fine.
• Do not panic during defrost. In cold, damp weather the outdoor unit will occasionally steam and whoosh as it melts frost off its coil. That is normal operation, not a failure.
• Keep the outdoor unit clear. Leaves, snow, and ice block airflow. Gently clear it; never chip ice off the coil.
• Mind the backup heat. Many systems have electric resistance backup that costs far more per hour to run. If your thermostat shows auxiliary heat constantly in mild weather, something needs adjustment.

Modern cold climate units hold their capacity well below freezing, and our guide to cold climate versus standard heat pumps explains what that means for the December 2022 scenario. A fall seasonal tune-up catches weak capacitors, low refrigerant, and dirty coils before the first cold night puts the system under real load.

How do you keep air healthy in a sealed-up house?

Winterizing seals the house, and a sealed Puget Sound house has a moisture problem waiting. Cooking, showers, and breathing add gallons of water vapor to indoor air every day, and in our climate that vapor condenses on cold window frames and wall corners and feeds mold. So while you seal, also ventilate deliberately: run bathroom fans during and for 20 minutes after showers, use the kitchen range hood whenever you cook, and crack windows briefly on dry days. If your windows drip every winter morning, the house needs mechanical ventilation, and our comparison of HRV versus ERV ventilation systems explains how to bring in fresh air without throwing away the heat you paid for.

What is the cold snap playbook?

When the forecast shows several days below freezing, run this sequence the day before it arrives.

1. Confirm hoses are off and bibs are covered.
2. Close or cover the crawlspace vents.
3. Open cabinet doors under sinks on exterior walls so room heat reaches the pipes.
4. Let a pencil-thin stream of cold water run at the faucet farthest from where water enters the house, and at any fixture with a freeze history.
5. Hold your heating setpoint steady, day and night, even overnight.
6. Know where your main water shutoff is and confirm it turns. If a pipe bursts, that valve is the difference between a repair and a disaster.

If you travel during a freeze, leave the heat at 55 or higher, keep the drip running, and have someone check the house. The worst losses we see are in empty homes where a burst pipe ran for days.

Common questions

When should I winterize a Puget Sound home?

Do the standing items, hoses, bib covers, pipe insulation, and a heating tune-up, by the end of October. The cold snap playbook items, dripping faucets and closing vents, only need to happen when a hard freeze actually shows in the forecast.

Do heat pumps really work in our winters?

Yes. Modern units heat effectively well below any temperature Puget Sound normally sees, and cold climate models keep strong output even in an arctic outbreak. The homes that struggled in December 2022 mostly had undersized or aging equipment, or resistance backup doing all the work at high cost.

Should crawlspace vents be open or closed in winter?

Open for the ordinary wet winter, because trapped moisture under the house causes rot and mold. Closed or covered only during hard freezes, to protect the pipes, then opened again when temperatures recover. The mistake is leaving them permanently in either position.

Is winterizing worth it if I rent out or rarely visit the property?

More so, not less. Unoccupied homes freeze first because nobody is running water or watching the thermostat. For a vacant property, consider shutting off the main water supply and draining the system before a freeze, and keep minimal heat on to protect what remains.

What to do next

Spend one October afternoon on the list: hoses off, bibs covered, crawlspace pipes wrapped, vents ready, shutoff valve tested. Then let the Eco team handle the mechanical side with a fall tune-up for your heating system so it is ready for the coldest week of the year. Book online or call (206) 970-1031. Real people answer early and late, 6 AM to 6 PM every day.