Winterizing a home that is still being repaired

These are the two states a building can safely spend a winter in. The expensive mistake is the middle — a house left with water in the pipes and no reliable heat. Which one you choose depends on whether the repair is active and whether the power is dependable.

• Repairs ongoing and power reliable: keep heat on, set no lower than 55°F.
• Repairs paused, or power uncertain: shut the water off at the main and drain the system.
• Whichever you choose, tell your insurer and your restoration contractor, because both of them plan around it.

A house that is half-heated and half-drained has the drawbacks of both.

Closing a valve is not draining a system. Water left in a low spot, a trap or a water heater will still split the pipe that holds it.

• Shut off the main, then open every faucet — highest in the house first, lowest last — and leave them open.
• Drain the water heater, and switch off its power or gas first so it cannot fire on an empty tank.
• Blow the lines out with compressed air if you can, because gravity alone leaves water in horizontal runs and bellies.
• Flush every toilet and sponge the tank and bowl out.
• Pour RV or plumbing antifreeze into every drain trap, every toilet bowl, and the washer standpipe — a dry trap also lets sewer gas back into the house.
• Do not put automotive antifreeze into plumbing.

Outside hose bibs, irrigation and any line to a shop or barn are the ones most often forgotten.

The wrong heater adds water to a building you are trying to dry, and can be dangerous in a house with nobody in it to notice.

• Use a vented heater that sends its exhaust outdoors, or the home’s own system if it is safe to run.
• Avoid unvented fuel-burning heaters: they release roughly half a gallon of water for every gallon of fuel burned, straight into a building being dried.
• Fit working carbon monoxide alarms, on every level, before running any fuel-burning heat.
• Open cabinet doors under sinks and on exterior walls so warm air reaches the pipes behind them.
• Keep interior doors open so heat reaches the whole floor plan rather than one room.

A furnace or water heater that was underwater is not a heat source until a licensed technician has passed it.

This is what makes a house in restoration different. Pipes that spent twenty winters inside an insulated wall are now sitting in an open cavity with nothing between them and the sheathing.

• Walk the house and note every run of pipe you can now see that you could not see before.
• Insulate those runs with foam sleeves, and use heat tape rated for the job where a run is badly exposed.
• Pay attention to crawl spaces, garages, exterior walls and anywhere the insulation came out.
• Close up open exterior penetrations — a missing vent cover or an open rim joist is a direct path for freezing air.

Pipes in unheated spaces and exterior walls freeze well before the outdoor temperature reaches 20°F.

This is the step people do not expect. Cold does not just risk pipes — it halts the drying that the whole repair is waiting on.

• Standard compressor dehumidifiers lose effectiveness below about 60°F and ice up when their coils drop below freezing, at which point they are moving air and removing nothing.
• In a cold building the right equipment is a low-temperature unit with auto-defrost, or a desiccant dehumidifier, which has no cold coil to ice up.
• Keep the building warm enough for the equipment to work, not merely warm enough to avoid a freeze.
• Let in some air exchange on milder days to carry moisture out.

A dehumidifier running in a 45°F room can look like progress for weeks while the structure stays wet.

Snow blowing into an open wall or a missing window does not wait for spring to become water.

• Cover open walls, roof openings and missing windows with sheeting, fastened to hold in wind.
• Clear snow that has already found its way in — roughly every 10 inches of snow holds about an inch of water.
• Keep gutters and downspouts clear so meltwater runs away from the foundation rather than back into it.
• Make sure the ground outside still slopes away from the house after the excavation and the repairs.

The parts of the property that stayed underground have their own winter, and a system disturbed by flooding is more fragile than it was.

• A septic system that was flooded should be inspected before winter rather than after it.
• Keep vehicles and equipment off the drain field — compacted and frozen soil damages it.
• Leave snow cover on the tank and field where you can; it insulates.
• If the house will sit unused, ask about the right way to leave the septic system over the winter.
• On a well, do not drink the water until it has been tested by a laboratory.