Skip to content
LoclisBeta
Sign up
UpkeepFrozen Pipe

How do I keep pipes from freezing in winter?

Keep the house warm, never below 55 degrees even when you are away, and hold the thermostat steady overnight in a hard freeze. Before winter, shut off and drain outdoor faucets and insulate pipes in crawl spaces, garages and outside walls. On the coldest nights, open sink cabinets and let a cold faucet drip. Know where your main shut-off valve is.

Free to ask. Local shops send quotes, and you pay only when you book one.

By Kasra Taheri, Founder, LoclisUpdated

Researched and drafted with AI, then checked claim by claim against the sources listed below before it was published. Prices and rules change; the dates beside each source say when it was last checked.

Step by step

Read when to stop and call a pro, further down this page, before you start.

  1. Step 1: Find and test the main shut-off

    Find the main water shut-off valve, tag it, and test that it closes before the first freeze.[3]

  2. Step 2: Disconnect hoses

    Disconnect garden hoses from the outdoor faucets, drain them and store them before the first hard freeze.

  3. Step 3: Drain the outdoor faucets

    Shut off and drain the pipes that lead to your outside faucets and hose bibs.[1][4]

  4. Step 4: Drain sprinkler lines

    Make sure irrigation and sprinkler systems are turned off and fully drained.[3]

  5. Step 5: Insulate exposed pipes

    Insulate the pipes in unheated or drafty areas such as the garage, crawl space, unheated rooms and cabinets on outside walls.[1][3]

  6. Step 6: Match the sleeve to the pipe

    Measure the pipe and buy sleeves whose inside diameter matches the pipe's outside diameter, for a snug fit.[5]

  7. Step 7: Protect yourself with fiberglass

    Wear gloves, goggles and a dust mask if you work with fiberglass insulation.[5]

  8. Step 8: Seal the drafts

    Seal air leaks in the crawl space and basement and around doors near water lines.[1][3]

  9. Step 9: Keep outside doors closed

    Keep doors and windows to the outside tightly closed in cold weather.[1]

  10. Step 10: Hold the thermostat steady

    Keep the thermostat at the same temperature day and night during a hard freeze.[2]

  11. Step 11: Open the sink cabinets

    Open kitchen and bathroom sink cabinets on cold nights, removing any toxic substances first if there are small children or pets.[1]

  12. Step 12: Let a cold faucet drip

    In a hard freeze, let a cold faucet drip, ideally the one highest in the house and farthest from the main shut-off.[1]

  13. Step 13: Leave the heat on when away

    Set the heat no lower than 55 degrees while you are away and ask someone to check the house.[1][2]

The short answer

Pipes freeze when cold air reaches water that is not moving. So the job is to keep the house warm, keep cold air away from the pipes, empty the lines you do not use in winter, and keep water moving on the worst nights. Most of it takes an afternoon in the fall and a few habits during a cold snap. Learn where your main shut-off valve is too, so a freeze that gets through costs a drip instead of a flood.

Before the first freeze

Find and test the main shut-off. Loudoun Water's advice: "Know where your main shut off valve is and label it."[1] Virginia American Water suggests closing it to test it: once completely closed, check sinks and other fixtures to make sure it is working,[3] and "If the valve does not close easily, it may need to be serviced."[3] Show everyone in the house where it is.

Empty the outdoor lines. Disconnect garden hoses, drain them and put them away. Then deal with the faucets they hang on. Loudoun Water: "Shut off and drain the pipes leading to your outside faucets and/or hose bibs so no water is left to freeze, expand and cause a leak in these lines."[1] Fairfax County Fire and Rescue gives the same advice for every unused line: "Shut off water to unheated areas of your home and to outdoor faucets. Don't forget to drain these pipes."[4] Virginia American Water adds that you should make sure sprinkler and irrigation systems are turned off and fully drained.[3]

Insulate the pipes in cold spaces. Check the garage, the crawl space, unheated rooms, and cabinets under sinks on outside walls. Loudoun Water: "Insulate pipes in any unheated or drafty areas."[1] Do both lines, since "Water freezing in your cold and hot water pipes can cause serious problems."[4] "Hardware and plumbing supply stores carry insulation to keep pipes from freezing."[1] The Department of Energy lists the forms: tubular pipe sleeves, spiral insulation wrap, and fiberglass batts that can be taped around the pipes.[5] For sleeves, it says to match the pipe's outside diameter to the pipe sleeve's inside diameter to ensure a snug fit.[5] If you use fiberglass, it warns: "Wear gloves, goggles, and a dust mask when working with fiberglass."[5] Where pipes are exposed to cold, Virginia American Water says to wrap them with insulation or heat tape, and notes that even fabric or newspaper can help.[3]

Copper water pipes above an open ceiling panel, one of them partly covered by white pipe insulation
Photo: Achim Hering, CC BY 3.0, via Wikimedia Commons

Stop the drafts. A draft blowing across a pipe is often what freezes it. Loudoun Water says to seal all leaks in crawl spaces and basements,[1] and Virginia American Water adds: "Fix drafty windows, insulate walls around pipes and plug drafts around doors."[3] In cold weather, Loudoun Water's advice is: "Keep doors and windows to the outside tightly closed."[1] That includes a garage door when water lines run through the garage.

Pipes in outside walls. These are the hardest to protect from inside the room. The Department of Energy's guidance for builders: "If pipes must be placed in exterior walls, ensure that the pipes are insulated and that suitable cavity insulation is installed behind the pipes".[5] Fairfax County Fire and Rescue notes that after a break you may consider having the pipe or pipes rerouted through less vulnerable areas,[4] which is a plumber's job.

During a cold snap

Keep the heat up and steady. Virginia Beach Public Utilities: "Keep your thermostat at the same temperature both day and night, so that pipes stay warm as the outside temperature dips overnight."[2] Loudoun Water's floor is to keep your thermostat set no lower than 55F,[1] home or away.

Open the cabinets. Loudoun Water: "Open the cabinets beneath any place with a water supply, such as the kitchen and bathroom sinks. This will allow warm air to circulate."[1] And: "Remove any toxic substances first if there are small children or pets in the home."[1]

Let a faucet drip. Loudoun Water suggests a trickle of cold water from the faucet that is the greatest distance from your main water shut off valve and at the highest point in your home.[1] Virginia Beach Public Utilities gives the reason: "Since moving water is less likely to freeze, allow a steady drip of cold water to flow from the highest faucet in your home."[2] Virginia American Water on the cost: "The cost of the extra water is typically lower than the cost of repairing a broken pipe."[3] It is not a cure-all. Fairfax County Fire and Rescue warns: "Leaving a faucet on with a slow trickle may or may not keep the pipe from freezing; you can't count on this method."[4]

Heat tape: use with care

For a pipe you cannot keep warm any other way, Fairfax County Fire and Rescue says: "There are some specially designed, UL approved heat tapes that can be used in unheated areas, but again, you need to be careful."[4] Its warning: "If these methods are used, be sure to follow the directions exactly; a slight variation could cause a fire."[4] Read the manufacturer's instructions before you buy, including what they say about covering the tape with insulation, and leave anything hard-wired to an electrician.

When you go away

Loudoun Water's warning: "Travelers will often make the mistake of turning their thermostats off thinking it will save on their heating bill when in reality, they'll come home to frozen pipes."[1] Virginia Beach Public Utilities says to set your thermostat no lower than 55 degrees Fahrenheit and have a friend or neighbor check on your home daily.[2] Before going out of town, it also suggests you shut off and drain the water system,[2] noting that if you have a fire protection sprinkler system in your house, it may be deactivated when you shut off the water.[2] The water heater is part of that system, so before you drain anything, check your water heater's manual or ask a plumber how to leave it while you are gone. Water heater work is a job for a licensed pro. Virginia American Water also suggests a freeze alarm, which calls a phone number you choose if the inside temperature drops below 45 degrees.[3]

Stop and call a pro if

  • A pipe freezes even after you have insulated it and kept the heat up. It may need rerouting.
  • Pipes run in an outside wall, an unheated addition or a crawl space you cannot get into.
  • Your main shut-off valve will not close, leaks, or is seized. A plumber can service or replace it.
  • A pipe has heat tape and froze anyway, or it needs a new hard-wired heating cable: that is a job for an electrician.
  • You plan to shut off and drain the house before a trip and are not sure how to leave the water heater: ask a plumber, or follow the water heater's manual.
  • A pipe has already frozen and split. Close the main and see when to call a plumber for frozen pipes.

If a pipe does freeze, read how to tell if your pipes are frozen and how to thaw a frozen pipe safely. You can also browse frozen pipe repair, find plumbers in Blacksburg, or see all plumbing repair answers.

To have a plumber insulate, reroute or repair a pipe, describe the job once and licensed local plumbers quote it.

Common questions

What temperature should I keep my house to stop pipes freezing?
Loudoun Water says to keep the thermostat set no lower than 55F whether you are home or away, and Virginia Beach Public Utilities gives the same floor for when you go out of town. In a hard freeze, Virginia Beach also says to keep it at the same temperature day and night rather than setting it back overnight.
Does dripping a faucet really work?
It helps but is not a sure thing. Virginia Beach Public Utilities says moving water is less likely to freeze, and Virginia American Water says the extra water typically costs less than repairing a broken pipe. Fairfax County Fire and Rescue cautions that a slow trickle may or may not keep the pipe from freezing, so pair it with heat and insulation.
Which faucet should I drip?
Loudoun Water's advice is the faucet that is the greatest distance from your main water shut-off valve and at the highest point in your home, using cold water. Virginia Beach Public Utilities also says to drip cold water from the highest faucet. Add any faucet whose pipes run through a cold spot.
Should I close my crawl space vents in winter?
Loudoun Water advises sealing all leaks in crawl spaces and basements, and cold air moving past pipes is what freezes them. If your crawl space has vents and you are unsure whether to close them, ask a plumber or a home performance contractor what suits your house.
Is heat tape safe?
Only when it is a product made for the job and used exactly as directed. Fairfax County Fire and Rescue says there are specially designed, UL approved heat tapes for unheated areas, but that you need to be careful and follow the directions exactly, because a slight variation could cause a fire.
What should I do before leaving for a winter trip?
Leave the heat on, no lower than 55 degrees, and have someone check the house. Before going out of town, Virginia Beach Public Utilities also suggests shutting off and draining the water system, noting that a home fire sprinkler system may be deactivated when the water is shut off. Before you drain the house, check your water heater's manual or ask a plumber how to leave the water heater; that part is a job for a pro. Virginia American Water suggests a freeze alarm that calls you if the house gets too cold.

Sources

  1. [1] Frozen Pipes, Loudoun Water. Checked October 26, 2026.
  2. [2] Prevent Frozen Pipes from Bursting Your Budget (December 15, 2025), City of Virginia Beach Public Utilities. Checked October 26, 2026.
  3. [3] Virginia American Water Urges Customers to Prepare for Cold Weather (December 3, 2025), Virginia American Water. Checked October 26, 2026.
  4. [4] Frozen Water Pipes, Fairfax County Fire and Rescue Department. Checked October 26, 2026.
  5. [5] Pipes in Exterior Walls, U.S. Department of Energy, Building Science Education. Checked October 26, 2026.

Want a pro to handle it?

Describe the job once. Licensed local businesses send quotes, and you pay only when you book one.