Winterize Your Plumbing: Prevent Frozen Pipes, Leaks, and Costly Repairs

By H.I.S. Plumbing

on August 21, 2025

Plumber installing foam insulation on exposed basement water pipes before a freeze

Each winter, frozen pipes cause leaks, water damage, and surprise repair bills. The good news: with a clear plan and a few low-cost upgrades, most freeze damage is preventable.

H.I.S. Plumbing handles emergency plumbing day and night, so we see what works in real homes. Use this step-by-step guide to get ready before the freeze, protect your plumbing during a cold snap, and thaw lines safely if they do freeze.

The Problem: Why Pipes Freeze and Burst

Water expands as it turns to ice. When water freezes inside a pipe, pressure builds between the ice plug and your closed faucet or valve. That pressure can split copper, PEX, or PVC—often after temperatures warm back up. The most at-risk lines are in unheated or poorly insulated areas:

Exterior walls, garages, crawl spaces, attics, and basements
Under sinks on exterior walls
Laundry areas near vents or doors
Hose bibs and irrigation lines
Sump pump discharge lines

Risk increases with wind chill, power outages, and sudden temperature drops. It only takes a small exposed section to freeze the entire run.

Before the Freeze ❄️

Winters are easier when you prep early. Focus on insulation, drainage, and equipment service.

Insulate Exposed Pipes; Use Heat Tape Where Appropriate

Wrap hot and cold water lines in unheated spaces (basements near rim joists, crawl spaces, garages, attics). Use foam sleeves or fiberglass with a vapor barrier. Seal seams and elbows with rated tape.
Insulate bends, tees, and valves—these are common weak spots.
Add pipe insulation where lines run through exterior wall cavities. If you’re remodeling, move them to interior walls when possible.
Heat cable (UL-listed only) can protect vulnerable runs. Follow the manufacturer’s instructions and the cable’s watt-density limits. Use a GFCI-protected outlet. Do not overlap cables.

Code note: The International Residential Code (IRC P2603.5) and Uniform Plumbing Code (UPC 609.3) require protection for water lines in areas subject to freezing.

Disconnect and Drain Outdoor Hoses; Winterize Hose Bibs

Remove garden hoses from spigots. Leaving hoses attached traps water and can crack the faucet and the pipe inside the wall.
Install or verify interior shutoff valves for exterior sillcocks. Close the inside valve, open the outside faucet to drain, then cap loosely or leave slightly open to prevent trapped water.
For standard (non-frost-free) hose bibs, add insulated covers after you drain the line. Frost-free faucets still need the hose removed to work properly.

If you have an irrigation system, schedule a blowout or drain-down before sustained freezing weather.

Shut and Drain Sillcock Lines

Locate the interior shutoff (often a stop-and-waste valve) that serves each hose bib.
Close the valve. Open the outside faucet and drain from the waste port on the interior valve if present.
Confirm no water drips when the outside faucet is fully open; if it does, your shutoff may be leaking and should be repaired.

Service Boilers and Water Heaters for Peak Performance

Water heaters: flush sediment, check the anode rod, verify the temperature and pressure relief (TPR) valve operates, and set the thermostat to 120°F unless a specific use requires higher temperature.
Boilers and hydronic systems: check system pressure, air vents, expansion tanks, and backflow prevention assemblies. In garages or outbuildings, a glycol mix (as designed) may be needed to protect loops from freezing. This requires proper backflow protection and testing.
Consider a maintenance check before winter. Efficient heat helps keep the whole house above freezing.

Authoritative guidance is available from product manufacturers, the American Society of Sanitary Engineering (ASSE) for backflow components, and your local building department.

During a Cold Snap 🌡️

When temperatures plunge, slow moving water and small adjustments can prevent big damage.

Maintain indoor temps: keep your thermostat no lower than 55–60°F, even if you’re away. Steady heat prevents cold pockets in walls and cabinets.
Open cabinet doors under sinks on exterior walls. This lets warm room air reach the pipes.
Let vulnerable fixtures drip: a slow cold-water drip (about a pencil-lead stream) relieves pressure and keeps water moving.
Protect attics, crawl spaces, and garages. Close vents and doors that let in wind. Add safe, temporary heat only if you can do so without fire risk and with proper ventilation.
Know your main shutoff: find it now. It’s usually where the water line enters the home. Label it. Make sure everyone in the house can operate it.
Power outage plan: if heat is off, shut the main and open the lowest fixture (like a basement sink) to drain pressure. Then open a faucet on the top floor to admit air and help water drain from lines.

Safety note: If you use space heaters, follow Consumer Product Safety Commission guidance—keep them at least 3 feet from combustibles, on a stable surface, plugged directly into a wall outlet (no extension cords), and never leave them unattended.

If Pipes Freeze 🔧

Stay calm and work methodically. Frozen doesn’t always mean burst.

Signs a Pipe Is Frozen

One or more fixtures stop flowing, especially on an exterior wall or above a crawl space.
You hear gurgling or see frost on exposed sections.
The water meter spins when fixtures are off (possible leak) or stops completely when it should flow.

Step-by-Step: Safe Thawing

Turn on a nearby faucet. A small trickle or open valve helps relieve pressure as ice melts.
Warm the pipe slowly. Use a hair dryer, heat gun on low, or a heating pad wrapped around the pipe. Start at the faucet end and work toward the frozen section. Keep the device moving to avoid overheating one spot.
Use UL-listed heat cable if installed. Follow the manual. Never overlap or insulate over a cable unless the manufacturer says it’s allowed.
Warm the space. Open cabinets and bring up the room temperature. Safe space heaters can help if monitored.
Never use open flames. No torches, no grills, no candles. Open flames can ignite framing and degrade solder joints and pipe materials. They also create deadly carbon monoxide.

Source guidance: The American Red Cross and local fire departments recommend using gentle, indirect heat and avoiding open flames.

If You Suspect a Burst

Shut off the main water immediately.
If you can safely access the frozen area, place a bucket or towels underneath before thawing.
Once thawed, watch for leaks. Check joints, elbows, and valves as water begins to flow.
If you find a leak, keep the main shut off and call H.I.S. Plumbing for emergency plumbing service.

After Thawing: Check and Reset

Inspect the meter box (if applicable) and the main valve area for leaks.
Slowly repressurize the system: open the main valve a quarter turn, listen, inspect, then fully open.
Run each faucet for 2–3 minutes to purge air. Clean aerators if flow sputters.
If water is discolored, flush cold lines first, then hot.

Quick Safety Checklist ✅

Use this quick pass before, during, and after a freeze.

Before:

Insulate exposed pipes, elbows, and valves; seal gaps where cold air enters.
Disconnect hoses; shut and drain hose bib lines.
Service your water heater and boiler; test sump pump operation.
Label the main shutoff; test fixture shutoff valves.

During:

Keep the home at 55–60°F or higher.
Open sink cabinets on exterior walls.
Drip vulnerable fixtures.
Avoid using space heaters near water; if used, plug directly into a GFCI-protected outlet and monitor.

If Frozen:

Open a nearby faucet and warm pipes slowly with safe heat.
Never use an open flame.
If you suspect a burst, shut off the main and call for emergency plumbing.

After:

Inspect for leaks at joints and behind access panels.
Check crawl spaces and basements for drips or pooled water.
Reset water pressure slowly and flush lines.

DIY vs. Call a Pro

Many prevention steps are DIY-friendly:

Pipe insulation, hose bib covers, and cabinet door adjustments
Weatherstripping around drafty rim joists and sill plates
Gentle thawing on easily reached, small sections

Call H.I.S. Plumbing when:

You can’t locate the frozen section or it’s behind a wall or ceiling.
The main or a branch line won’t thaw with gentle heat in 30–45 minutes.
You see bulging pipes, a split seam, or any active drip.
You need heat cable calculated and installed to code.
You’re dealing with gas-fired equipment, boiler loops, or backflow assemblies.
You want code-compliant upgrades like additional shutoff valves, recirculation loops, or repiping.

If you’re searching for Emergency Plumbing near you, we’re equipped for fast response, clean work, and code-compliant repairs.

What Pros Do On Arrival

Here is what our licensed technicians typically perform on a freeze call:

Rapid assessment: locate the main shutoff, verify meter function, and check for pressure drops.
Thermal imaging and moisture readings: identify hidden ice plugs and wet areas behind walls and ceilings.
Controlled thawing: apply safe heat methods, isolate sections with shutoffs, and prevent pressure spikes during melt.
Leak detection: pressure testing and dye tabs to confirm integrity before full restoration of flow.
Repairs: cut out split sections, replace with appropriate material (copper, PEX, or CPVC per code), and install new shutoffs where helpful.
Cleanup and protection: install proper pipe supports, insulation, and draft sealing. If needed, coordinate with water mitigation professionals for drying.

We follow manufacturer instructions, IRC/UPC requirements, and local amendments for materials, insulation, and freeze protection.

Prevention & Maintenance 💡

Small upgrades make a big difference when temperatures drop.

Seal air leaks. Cold drafts freeze pipes faster than steady cold. Look for gaps around hose bib penetrations, cable entries, dryer vents, and sill plates. Use foam, caulk, or fire-rated sealants where required.
Add insulation where it counts. Insulate rim joists and knee walls. Keep insulation between the pipe and the cold exterior, not between the pipe and the room.
Exercise valves. Turn fixture shutoffs and the main off and on twice a year to keep them operable.
Service equipment. Annual water heater and boiler service reduces surprise outages on the coldest day.
Test sump pumps. Pour water into the pit and verify discharge. Insulate or heat-tape exposed discharge runs that travel outdoors.
Check water pressure. High pressure stresses fittings and can worsen burst damage. Install or service a pressure-reducing valve if your pressure exceeds 80 psi.

Long-Term Upgrades

Consider these improvements if your home has a history of frozen pipes:

Add shutoffs and drain points: isolate at-risk branches so you can quickly drain them before a storm.
Install hot water recirculation lines: gentle circulation keeps hot lines warmer and reduces wait time at faucets.
Smart leak detectors: place sensors near water heaters, under sinks, and by laundry. Some systems auto-shut off the main when a leak is detected.
Re-route lines: move plumbing away from exterior walls into conditioned space during remodels.
Frost-free hose bibs: replace standard spigots and add interior stop-and-waste valves if they’re missing.
Upgrade materials: modern PEX with proper fittings and supports may handle minor freezing better, though no pipe is freeze-proof without protection.
Add insulation and heat in cold zones: in crawl spaces or garages with plumbing, a small, code-approved heat source with a low-temperature thermostat can prevent recurring freezes.
Backflow prevention and testing: ensure boiler fill and irrigation systems have proper backflow devices and are tested per local rules.

Costs & Time Factors 💵

Actual costs vary by home, access, materials, and local codes. These ranges are typical:

Pipe insulation: about $2–$5 per linear foot installed, more for tight spaces or complex runs.
UL-listed heat cable: roughly $2–$8 per foot of cable, plus installation.
Hose bib replacement (frost-free): $150–$400 per faucet depending on access.
Leak detection and thawing: 1–3 hours for simple freezes; complex or hidden lines can take longer.
Burst pipe repair: small accessible sections may run $300–$1,500; larger or concealed runs cost more due to drywall/finish work.
Water heater service: commonly 60–120 minutes depending on sediment and access.
Whole-home repiping: highly variable, often several thousand dollars depending on size, materials, and finishes.
Water damage drying and restoration: ranges widely; even minor drywall and flooring repairs can add $1,000–$5,000+.

Time is a factor. The sooner you call when a line freezes or bursts, the smaller the repair and the lower the restoration costs tend to be.

When It’s an Emergency 📞

Shut off the main and call H.I.S. Plumbing if:

You hear water running with fixtures off.
You see a visible split, bulge, or spraying line.
Ceilings sag, walls soften, or flooring buckles.
The main sewer backs up or a sump discharge line is frozen and water is rising.
A water heater or boiler leaks from a relief valve or tank seam.

We handle emergency plumbing, leak detection, pipe repair, unclogging toilets, water heater repair, sump pump repair, and more—24/7. If you need Emergency Plumbing near you now, we’re ready.

Before the Freeze: Your Detailed Prep Plan

Use this pre-season list to winterize without guesswork.

Inventory vulnerable spots: note every sink on an exterior wall, pipes in unheated spaces, and long runs to detached garages or additions.
Insulate strategically: prioritize the coldest sections and elbows. For fiberglass wrap, add a vapor barrier to prevent condensation. For foam tubes, match diameter to pipe size and seal seams.
Heat cable design: measure the run, include two-thirds of vertical rises and all valves. Use only cable approved for the pipe type (plastic vs. metal). Install with GFCI protection and a thermostat if recommended by the manufacturer.
Weather-seal access points: foam gaskets behind exterior wall outlets/switches, seal around hose bib and cable penetrations, add door sweeps on drafty basement doors.
Drain outside water: hoses, irrigation, and decorative fountains.
Appliance check: clean dryer vents (cold air intrusion), inspect washing machine hoses, and make sure the laundry area is warm enough.
Water heater flush: drain a few gallons to check sediment; full flush if needed. Verify TPR valve operation per manufacturer guidance.
Boiler readiness: verify system pressure, purge air, and test low-water cutoffs and backflow prevention. Consider glycol protection for outbuilding loops if designed for it.
Test alarms: install or test carbon monoxide detectors and water leak sensors. Replace batteries.

Authoritative references: International Residential Code and Uniform Plumbing Code (freeze protection), manufacturer instructions, Consumer Product Safety Commission (space heater safety).

During a Cold Snap: Keep Water Moving

These simple habits work:

Let cold water drip at far fixtures. Moving water freezes slower.
Protect the room air path. Open vanity and kitchen doors. Remove stored items that block warm air.
Circulate air. Ceiling fans on low in reverse can pull warm air down.
Avoid deep nighttime setbacks. Rapid temperature drops inside walls can outpace recovery.
Garage rule: keep doors closed if any plumbing runs through the space.
Crawl space hatches: if your lines run there, keep the hatch closed and consider a safe, low-wattage heat source if permitted.

If your home is vacant or a vacation property:

Shut the main valve and consider draining the system, including the water heater (turn off power or gas first). Add non-toxic RV antifreeze to traps and toilets. This process is best handled by a licensed plumber.

If Pipes Freeze: The Emergency Playbook

Locate your main shutoff. Know if it’s a wheel valve, ball valve, or curb stop.
Open a nearby faucet to relieve pressure.
Apply gentle heat. Start at the faucet and move toward the suspected ice. Keep cords away from water.
Monitor for leaks. If thawing restores flow, inspect carefully. Look and listen.
If you find any wet spots, stop. Shut the main and call H.I.S. Plumbing. We can isolate the section, repair it, and get you back online.

Extra care zones:

Behind tubs and showers on exterior walls
Kitchen sinks with deep cabinets packed with items
Laundry rooms over garages
Finished basements with soffits hiding pipes

FAQ ❓

Q: How cold does it have to be for pipes to freeze?
A: Risk starts near 20°F (-6°C) for several hours, but wind and drafts can cause freezing at higher temperatures. Uninsulated lines near outside air can freeze fast.

Q: Should I drip hot or cold water?
A: Drip cold water at the most vulnerable fixture. Cold uses less energy and still keeps water moving. In very cold homes, trickle both hot and cold to protect both lines.

Q: Can PEX freeze without bursting?
A: PEX can tolerate some expansion, but fittings and valves can still crack, and repeated freezes weaken materials. Protection is still needed for PEX.

Q: Is heat tape safe?
A: Use only UL-listed heat cable designed for your pipe type. Install per instructions, on GFCI, and never overlap. Inspect yearly and replace when worn.

Local and Seasonal Considerations

Freeze protection varies by climate and construction:

Snowbelt and high-elevation homes: deeper frost lines, stronger winds, and longer cold snaps. Insulate more aggressively and consider heat cable for known trouble spots. Verify your insulation R-values in rim joists and attics.
Mixed climates: swings from warm to arctic air can be more damaging than steady cold. Pay attention to wind directions that drive air into crawl spaces and eaves.
Older homes: uninsulated walls, balloon framing, and hidden chases can act like chimneys for cold air. Air sealing is as important as pipe insulation.
Newer homes: tighter envelopes help, but long plumbing runs to island sinks, bonus rooms, and over-garage spaces need attention.
Local codes: frost depth and insulation requirements vary. Your building department can confirm local frost depth and any special amendments. Follow IRC/UPC and local rules for insulation, heat cable, and backflow prevention.

Seasonal checklist by month:

Early fall: schedule boiler/water heater service, test sump pump, plan any repiping or rerouting.
Late fall: insulate, install hose bib covers, drain irrigation, add smart leak sensors.
First cold snap: open cabinets, drip fixtures, confirm you can reach your main shutoff.
Mid-winter: re-check insulation and cable connections, replace any soaked or compressed insulation.
Spring: inspect for hidden damage, consider permanent upgrades while access is easier.

Extra Tips for Specific Fixtures and Systems

Toilets on exterior walls: a small drip at the nearby vanity sink helps. Insulate the wall cavity if remodeling, and avoid placing the tank snug against an uninsulated exterior wall.
Kitchen islands: long runs under slabs or through unheated spaces may need insulation sleeves or heat cable designed for the material.
Sump discharge: slope lines properly, avoid dips that hold water, and protect exposed sections with heat cable and insulation where permitted.
Water filtration and softeners: protect bypass valves and housings in basements or garages. Follow manufacturer winterizing instructions if draining.
Gas lines and safety checks: keep combustion air pathways clear. Do not enclose water heaters or boilers so tightly that you starve them of air. Install and test CO alarms.
Backflow prevention: irrigation and boiler fill assemblies need proper protection and periodic testing.

Code and Safety Notes

Freeze protection is called out in the International Residential Code (IRC) and Uniform Plumbing Code (UPC). Local amendments may be stricter—always follow local rules.
Use UL-listed heat cable and GFCI protection for powered devices.
Use only noncombustible insulation near heat sources where required.
Follow Consumer Product Safety Commission guidance for space heaters.
Manufacturer instructions govern installation and operation for water heaters, boilers, and heat cable.

When to Upgrade vs. Repair

If you’ve had more than one freeze event:

Add section shutoffs and drain points to isolate cold branches.
Reroute lines during any remodel to interior walls.
Add a recirculation loop if hot water waits are long and lines cross cold spaces.
Install smart leak shutoff at the main; some systems monitor temperature and flow.
Consider partial repiping with better routing and support. Freeze protection is about both materials and layout.

The Bottom Line

Prevention beats cleanup. A few hours of insulation, sealing, and planning can stop days of disruption and high repair bills. If a line does freeze, use safe heat, go slow, and be ready to shut the main. When in doubt, call H.I.S. Plumbing. We provide emergency plumbing, leak detection, pipe repair, water heater services, sump pump repair, and more—with licensed techs and code-compliant solutions that hold up when the next cold snap hits.

Call H.I.S. Plumbing now — or reach us anytime at 1-888-778-7167 .