If you own a second home, rental property, cottage, cabin, or any house that will sit empty during freezing weather, learning how to winterize plumbing in a vacant house is one of the most important maintenance tasks you can do. When temperatures drop, standing water inside pipes, toilets, traps, faucets, and appliances can freeze, expand, and cause burst pipes, flooding, mold, structural damage, and expensive repairs. Winterization is especially important in a vacant property because no one is there daily to notice a falling indoor temperature or a small leak before it becomes a major problem .
Winterizing a vacant house means shutting off, draining, insulating, and protecting the plumbing system so it can safely sit unused through cold weather. In simple terms, winterization removes water from the plumbing system to help prevent freezing damage . Below is an educational, homeowner-friendly guide to help you prepare your vacant property the right way.
Why Winterizing Plumbing in a Vacant House Matters?
A vacant home is more vulnerable in winter because there may be no heat usage, no running water, and no one available to catch early warning signs. A pipe can freeze inside a wall, attic, crawl space, basement, garage, or exterior wall cavity. Once frozen water expands, it can crack the pipe. When the ice thaws, water can pour into the property for hours or days.
Professional winterization helps prevent burst pipes, flooding, water damage, and costly emergency plumbing repairs. This is why winterizing is recommended for houses, cabins, cottages, and vacation homes that will be left empty during cold months .
Step 1: Decide Whether the Water Will Stay On or Be Shut Off
Before you start, decide whether you plan to turn off and drain the water supply or keep the home heated with water running as normal. If the water is staying on, the heating system should also remain on to reduce the risk of frozen indoor pipes . Many homeowners set the thermostat to a safe low temperature rather than turning heat off completely.
However, if the property will be vacant for an extended time, the safest approach is usually to shut off the main water supply and drain the plumbing system. This reduces the chance of a catastrophic leak if a pipe, appliance hose, or fitting fails while no one is home.
Step 2: Shut Off the Main Water Supply
Find the main water shut-off valve and turn it off. In many homes, this valve is located in a basement, utility room, crawl space, garage, or near where the water line enters the property. If the home has municipal water, shutting off the main valve stops water from entering the house.
If the property uses a well, turn off power to the well pump at the circuit breaker before draining the system. Homes with well water may require additional winterization steps, including draining the pump according to manufacturer instructions or hiring a plumber to handle it properly .
Step 3: Drain All Water Lines
Once the main water supply is off, open every faucet in the house. Start with the highest fixtures first, then work your way down to the lowest fixtures. Open both hot and cold handles. This allows water to drain out of supply lines.
Do not forget:
- Kitchen faucets
- Bathroom sinks
- Bathtubs and showers
- Laundry sink faucets
- Basement faucets
- Utility room fixtures
- Outdoor hose bibs
- Bar sinks or wet bars
Leave faucets partially open after draining so any remaining moisture has room to expand if it freezes. Outdoor water lines and hose bibs should also be shut off, drained, and protected with insulation where needed .
Step 4: Drain the Water Heater
Turn off the power or fuel supply to the water heater before draining it. For an electric water heater, switch off the breaker. For a gas water heater, follow the manufacturer’s instructions and set the gas control appropriately.
Attach a garden hose to the drain valve at the bottom of the water heater and direct the hose to a safe drainage area. Open the drain valve and allow the tank to empty. Opening a hot water faucet in the home can help air enter the system and improve draining.
This step is important because water heaters hold a large volume of water. If that water freezes or the tank fails while vacant, the damage can be severe.
Step 5: Flush Toilets and Protect Toilet Traps
After shutting off the water, flush every toilet to remove as much water as possible from the tank and bowl. Use a sponge, towel, or wet/dry vacuum to remove remaining water from the tank and bowl.
Next, add non-toxic plumbing antifreeze to toilet bowls and traps. Do not use automotive antifreeze because it is toxic and not appropriate for household plumbing systems. Plumbing or RV antifreeze is designed for winterizing drain traps and fixtures.
This matters because even after draining the supply lines, water can remain in toilet traps and fixture traps. Pouring antifreeze into plumbing fixture drains helps protect standing water in P-traps from freezing .
Step 6: Add Antifreeze to Drains and P-Traps
Every sink, shower, bathtub, floor drain, and laundry drain has a trap that holds water to block sewer gases from entering the home. In winter, that trapped water can freeze if the property is unheated.
Pour non-toxic plumbing antifreeze into:
- Sink drains
- Shower drains
- Bathtub drains
- Floor drains
- Laundry standpipes
- Utility sink drains
- Toilet bowls
- Toilet tanks, if needed
This is a key part of winterizing plumbing in a vacant house because drain traps often retain water even after the rest of the system has been drained .
Step 7: Insulate Exposed Pipes
Even if you drain the plumbing, insulating vulnerable pipes adds another layer of protection. Focus on pipes in unheated or poorly insulated areas such as basements, crawl spaces, attics, garages, exterior walls, and utility rooms.
Use foam pipe insulation, fiberglass insulation, or approved heat tape where appropriate. Heat tape can help protect pipes from freezing when water remains in the system or when certain sections are difficult to fully drain . Attic insulation is also important because ice, snow, and cold air can affect pipes running through upper parts of the home .
Step 8: Winterize Outdoor Plumbing
Outdoor plumbing is highly exposed to freezing temperatures. Disconnect and drain all garden hoses. Shut off interior valves feeding outdoor faucets if your home has them. Open the outside faucets to release remaining water.
If the property has an irrigation system or sprinkler system, it may need to be blown out with compressed air. Sprinkler systems often require a specific draining process to avoid damage . If you are unsure, hire a professional irrigation or plumbing technician.
Also check outdoor kitchens, pool houses, detached garages, and guest houses. Any water line connected to the property needs winter protection.
Step 9: Check Appliances Connected to Water
Many vacant homes still have appliances that hold or use water. These should be drained or winterized according to manufacturer instructions.
Check:
- Washing machines
- Dishwashers
- Refrigerators with ice makers
- Water filtration systems
- Water softeners
- Humidifiers
- Boilers
- Sump pumps
Disconnect supply hoses where practical and drain them. For refrigerators with ice makers or water dispensers, shut off and drain the supply line. If the home uses a boiler or hydronic heating system, contact a qualified professional before draining anything, because those systems require specialized handling.
Step 10: Keep Some Heat On If Necessary
If the home will not be fully drained, keep the heating system running at a safe low setting. Keeping heat on may cost money, but it can help prevent internal pipes from freezing . This is especially important in homes with complex plumbing layouts, finished basements, pipes in exterior walls, or heating systems that rely on water.
Even in a drained property, keeping minimal heat can protect building materials, reduce condensation, and support overall home preservation.
Step 11: Seal Drafts and Inspect the Building Envelope
Plumbing winterization is not only about pipes. Cold air entering through gaps, cracks, vents, crawl spaces, broken windows, or poorly sealed doors can quickly lower indoor temperatures.
Before leaving the house vacant:
- Seal gaps around doors and windows
- Close foundation vents if appropriate for your region
- Repair broken glass
- Add weatherstripping
- Clean gutters
- Check roof leaks
- Insulate attic access points
Preparing the home for winter may include sealing air leaks, insulating exposed plumbing, cleaning gutters, and setting the thermostat safely . These steps help protect both the plumbing and the structure.
Step 12: Schedule Periodic Property Checks
Even after winterization, a vacant house should be checked regularly. Severe storms, power outages, furnace failures, roof leaks, and unexpected plumbing issues can still happen. Having a trusted neighbor, property manager, or maintenance professional inspect the home can prevent small problems from becoming expensive disasters.
During each check, look for:
- Unusual odors
- Signs of leaks
- Furnace or thermostat issues
- Frozen areas
- Water stains
- Broken windows
- Pest activity
- Sump pump problems
Even careful winter preparation cannot guarantee that nothing will go wrong in a vacant house , so routine monitoring is a smart safety measure.
Common Mistakes to Avoid
When learning how to winterize plumbing in a vacant house, avoid these common errors:
- Turning off heat without draining the plumbing
- Forgetting outdoor faucets
- Leaving hoses connected
- Not draining the water heater
- Ignoring toilet bowls and P-traps
- Using automotive antifreeze
- Forgetting appliances with water lines
- Failing to winterize well pumps or irrigation systems
- Assuming insulation alone is enough
- Not checking the property during winter
The goal is to remove or protect water anywhere it may freeze.
Should You Hire a Professional?
Some homeowners can winterize a simple plumbing system themselves, especially if they are comfortable shutting off valves, draining fixtures, and adding plumbing antifreeze. However, hiring a professional is wise if the property has a well, boiler, sprinkler system, multiple bathrooms, older pipes, crawl-space plumbing, or a history of freezing problems.
A licensed plumber can use compressed air to blow out lines, properly protect traps, inspect vulnerable areas, and confirm the home is ready for freezing temperatures. The cost of professional winterization is usually far less than the cost of repairing burst pipes and water damage.
Conclusion
Knowing how to winterize plumbing in a vacant house is essential for protecting your property during cold weather. Start by shutting off the water, draining supply lines, emptying the water heater, protecting toilets and P-traps with non-toxic plumbing antifreeze, insulating exposed pipes, winterizing outdoor plumbing, and arranging regular property checks. A well-prepared vacant home is far less likely to suffer frozen pipes, flooding, and expensive winter damage.
For more inspiration on keeping your property beautiful, functional, and comfortable year-round, you can also explore Home Comfort Experts. The website provides helpful ideas on home design, home decor, and home improvement, making it a useful resource for homeowners who want to improve both comfort and style. See more.