Burst pipes are one of the most expensive and stressful winter disasters a homeowner can face. A single burst can release hundreds of gallons of water per hour, causing tens of thousands of dollars in damage in minutes. The good news? Nearly all frozen-pipe incidents are preventable. By taking a few hours to properly winterize your plumbing before the first hard freeze, you can save yourself massive headaches (and repair costs) later.
Here’s your complete, step-by-step guide to winterizing your home’s plumbing system.
1. Understand Why Pipes Burst in Winter
Water expands by about 9% when it freezes. When water trapped inside a pipe turns to ice, that expansion creates enormous pressure — up to 2,000 psi in some cases — enough to split copper, PEX, or even steel. The pipe doesn’t always burst where the ice forms; it often splits at the weakest point, which could be far from the frozen section. That’s why prevention is so much easier than repair.
2. Start with an Outdoor Checklist
Shut off and drain outdoor faucets (hose bibs)
- Locate the shut-off valve inside your house for each outdoor faucet (often in the basement or crawl space).
- Turn the valve to the off position.
- Go outside and open the exterior faucet to drain remaining water.
- If your hose bib is a frost-free model (the valve seat is 8–12 inches inside the house), simply shutting it off and leaving the faucet open is usually enough. For non-frost-free bibs, consider installing frost-proof sillcocks before next winter.
Disconnect and drain garden hoses Store hoses indoors or in a garage so they don’t trap water that can back-flow into the pipe.
Drain and shut down sprinkler/irrigation systems Use the system’s drain valves or hire a professional to blow out lines with compressed air (highly recommended — DIY mistakes can be expensive).
3. Protect Pipes Inside the Home
Insulate exposed pipes Focus on pipes in unheated areas:
- Basements and crawl spaces
- Attics
- Garage walls
- Under kitchen/bathroom cabinets on exterior walls
Best insulation options:
- Foam pipe sleeves (cheap and easy)
- Heat tape or heat cable (for extremely cold climates or known problem pipes)
- Fiberglass wrap with vapor barrier
Tip: Slit foam sleeves lengthwise, slip them over the pipe, and seal with duct tape or zip ties.
Seal air leaks Cold air sneaking in through gaps can drop pipe temperature rapidly. Use caulk or spray foam to seal:
- Holes where pipes enter the house
- Cracks around windows and doors near plumbing
- Rim joists in basements
Keep the heat on (even when you’re away) Set your thermostat no lower than 55°F (13°C). This is the single most effective thing vacationers forget. Yes, it costs a little more in heating, but it’s far cheaper than flood damage.
Open cabinet doors under sinks On very cold nights, open vanity and kitchen sink cabinets so warm room air can circulate around the pipes.
Let faucets drip during extreme cold A tiny trickle of water (even a pencil-lead size) prevents pressure buildup if the pipe starts to freeze. Focus on faucets farthest from the main water entry.
4. Special Situations & Advanced Protection
Vacant or seasonal homes If the house will be unoccupied for weeks:
- Shut off the main water valve.
- Drain the entire system: open all faucets (hot and cold), flush toilets, and open the lowest drains (usually in the basement).
- Pour RV/marine antifreeze (pink, non-toxic) into all drains, toilet tanks, and traps. Never use automotive antifreeze — it’s toxic.
Manufactured/mobile homes The underside is especially vulnerable. Use heated skirts or heat tape under the home, and insulate the floor if possible.
Heat tape/cable installation tips
- Only use UL-listed products with built-in thermostats.
- Wrap carefully according to manufacturer instructions (usually spiral or straight run).
- Never cross the tape over itself.
- Plug into a GFCI-protected outlet.
5. What to Do If You Think a Pipe Is Frozen (But Hasn’t Burst Yet)
- Turn on the faucet — if only a trickle comes out, the pipe is likely frozen.
- Open the faucet fully so melting ice can escape.
- Apply gentle heat: hair dryer, heating pad, or towels soaked in hot water. Never use an open flame.
- Start warming closest to the faucet and work toward the suspected freeze point.
- Keep applying heat until full water pressure returns.
- If you can’t locate or thaw the pipe, call a plumber immediately.
6. When Disaster Strikes: What to Do If a Pipe Bursts
- Shut off the main water valve immediately.
- Turn off the electricity if water is near wiring.
- Call a plumber and your insurance company.
- Start water removal as quickly as possible (shop vac, fans, dehumidifiers).
Final Pre-Winter Checklist
- Insulate all exposed pipes
- Seal drafts and air leaks
- Shut off and drain outdoor faucets & irrigation
- Disconnect hoses
- Test heat tape (if using)
- Set thermostat to at least 55°F when away
- Know where your main shut-off valve is (and make sure it works!)
Taking these steps now will give you peace of mind all winter long — and keep your plumbing safe from the number-one cold-weather threat.
FAQ – Winterizing Your Plumbing
Q: Do I really need to winterize if I live in a mild climate? A: Yes, if temperatures ever drop below 20°F (−6°C) for 6+ hours. Even one cold snap can cause a burst. Many southern U.S. states see huge insurance claims every few years because homeowners assume “it never gets that cold here.”
Q: Is it safe to use automotive antifreeze in drains? A: No. Automotive antifreeze (ethylene glycol) is highly toxic. Use only propylene glycol-based RV/marine antifreeze (the pink kind) in drains and toilets.
Q: My pipes are PEX — do they still need winterizing? A: PEX is more freeze-resistant than copper or galvanized, but it can still split or fittings can fail. Always insulate and follow the same precautions.
Q: How much does professional winterization cost? A: Sprinkler blow-outs typically run $75–$150. Full-home winterization for vacant properties usually $150–$400 depending on size and location.
Q: Can I just turn off the water and skip draining when I leave for vacation? A: No. Water left in the system can still freeze and burst pipes. You must drain the system or keep heat on.
Useful Links & Further Reading
- Wikipedia – “Frozen Pipes and Prevention” → https://en.wikipedia.org/wiki/Water_pipe#Freezing
- Medium – “The Homeowner’s Guide to Surviving a Polar Vortex” → https://medium.com/@homeexpert/the-homeowners-guide-to-surviving-a-polar-vortex-2024-edition
- Red Cross – Winter Home Preparation Checklist → https://www.redcross.org/get-help/how-to-prepare-for-emergencies/types-of-emergencies/winter-storm.html
Stay warm, stay dry, and winterize your plumbing before Old Man Winter shows up!