Winterizing a seasonal home is a critical task that prevents thousands of dollars in damage from frozen pipes, ice damage, and moisture problems. Relying on electric heat set to 50°F is expensive and unreliable, especially in areas prone to winter storms that can knock out power for days.
The Risks of Leaving a House Heated But Unoccupied
A power outage during a winter storm causes interior temperatures to drop rapidly. Once below freezing, pipes begin to freeze within hours. The resulting burst pipes can cause tens of thousands of dollars in water damage.
| Interior Temp (°F) | Time to Freeze (0°F outside) | Risk Level |
|---|---|---|
| 55 | 8 to 12 hours | Low (with heat active) |
| 45 | 4 to 8 hours | Moderate (if power fails) |
| 35 | 2 to 4 hours | High |
| 30 and below | 30 to 60 minutes | Critical pipes will freeze |
Step 1: Shut Off Gas and Propane
Close the main gas shutoff valve where the service enters the house. Also close valves at each gas appliance including stoves, space heaters, water heaters, and furnaces. If you have a propane construction-of-sedimentation-tank-with-calculations/” target=”_blank”>tank, shut the valve at the tank.
Step 2: Drain the Water System
A. Power Down
Cut power to the water pump at the circuit breaker. For well pumps, turn off the dedicated breaker.
B. Drain the Water Heater
Attach a hose to the drain valve at the bottom of the tank. Open the drain valve and the pressure relief valve. For electric water heaters, verify power is off before draining.
C. Open All Faucets
Open every faucet hot and cold. Leave them open. Flush each toilet holding the handle down to empty the tank. Remove standing water from bowls and P-traps.
D. Address Trapped Water
Identify low points where water cannot drain by gravity. Install in-line drain valves at these locations.
Step 3: Protect Drain Traps
Pour approximately one cup of nontoxic RV antifreeze into each drain, including kitchen sinks, bathroom sinks, tubs, showers, and floor drains. Do not use automotive antifreeze, which is toxic.
| Antifreeze Type | Safe for Plumbing? | Toxicity |
|---|---|---|
| RV/Marine propylene glycol | Yes | Low (nontoxic) |
| Ethylene glycol (automotive) | No | High (toxic) |
| Denatured alcohol | Not recommended | Moderate |
Step 4: Create a Winterization Checklist
Document every step in a written checklist. Include the location of every shutoff valve, drain point, and appliance. Keep the checklist with the house for spring recommissioning.
Spring Recommissioning
Reverse the winterization steps in order. Check that all faucets are closed, then slowly open the main water valve. Inspect each connection for leaks before using fixtures. Check all accessible plumbing for leaks during the first 24 hours.
Additional Considerations
- Check roof snow load periodically during heavy snow winters
- Remove firewood from inside to prevent rodent infestation
- Seal all exterior openings larger than 1/4 inch
- Leave refrigerator and freezer doors slightly ajar to prevent mold
Conclusion
Complete draining of all water systems, protection of drain traps with nontoxic antifreeze, and secure shutoff of gas and electricity will protect your home through the harshest winter conditions.