The Empty House Problem: Why Seasonal Properties Fail in Winter
Published
Leaving the heat at 55°F depends on uninterrupted power and a working furnace, and the whole failure mode of vacant properties is that one of those stops while nobody is there. Full winterization drains the system so there is nothing to freeze.
Why vacant-property failures are the expensive ones
An occupied house that suffers a burst pipe has someone there to hear it, shut the water, and stop the damage within minutes. A vacant seasonal property has nobody, and the water runs until someone happens to visit.
In Maine, Vermont, New Hampshire, and the mountain counties of Colorado, Montana, and Wyoming, this is the defining winter plumbing risk. A burst line in an unoccupied camp can run for days or weeks. The resulting claims are among the largest in residential insurance.
Why the thermostat approach fails
Setting the heat to 55°F is reasonable for a short absence in an otherwise occupied house. As a strategy for a property standing empty through an entire winter, it is a bet that the power will never go out and the furnace will never fail.
In rural and mountain areas, extended winter power outages are routine rather than exceptional, and they happen during exactly the storms that produce the deepest cold. The strategy fails precisely when it is being tested.
What full winterization involves
The principle is simple: if there is no water in the system, there is nothing to freeze.
Shut off the water at the main
Close the main supply valve, and the meter valve if you have access.
Drain the entire system
Open every faucet from highest to lowest, open low-point drains, and flush every toilet to empty the tanks.
Drain the water heater
Cut its power or gas first, then drain the tank completely.
Blow out the lines
Low-pressure compressed air clears what gravity leaves in horizontal runs. This is the step amateur winterizations skip.
Antifreeze in every trap
Non-toxic RV antifreeze into sink, tub, shower, and floor drain traps, and into toilet bowls and tanks.
Arrange periodic checks
Many insurance policies require them for vacant properties in winter, and they catch problems early regardless.
The insurance clause that catches people
Most homeowners policies specifically exclude freeze damage in a property left vacant without heat or without the plumbing system being drained. That exclusion exists precisely because insurers know how this failure mode works.
A claim on an unwinterized seasonal property can be denied on the terms of the policy you already have. Check the language before winter, not after.