Every winter, social media fills up with short clips that promise simple ways to stop pipes from freezing. One repeating claim is that running hot water through pipes will keep them safe no matter how cold it gets. In some versions, people even warn that using hot water incorrectly will somehow “make pipes explode.” Both versions ignore what plumbers actually say.

Running hot water can sometimes help thaw a lightly frozen section of pipe, but it is not a magic shield against freezing, and it is not the main method professionals recommend. It wastes water and energy and still leaves exposed sections at risk. Real protection comes from insulation, sealing drafts, maintaining indoor heat, and letting water slowly move through at-risk lines when it is extremely cold.

What the Myth Says

The oversimplified version of the claim usually boils down to this:

• “If you just run hot water, your pipes cannot freeze.”
• “You do not need insulation or any other preparation.”
• Or, in the scare-story version, “Turning on hot water at the wrong time in a freeze will make pipes burst.”

These posts are attractive because they offer a single easy trick. Unfortunately, freezes do not care about shortcuts.

What Actually Causes Pipes to Burst

Pipes do not usually burst at the point where ice first forms. As water in the pipe freezes, it expands and creates pressure between the ice and a closed valve or another blockage. When that pressure gets high enough, the pipe fails at a weak point and splits. When the ice finally thaws, water can pour out of that split and cause significant damage.

What Plumbers Really Recommend

Plumbing pros and home safety guides tend to give very similar advice:

• Insulate exposed pipes, especially in unheated spaces such as attics, crawlspaces, and exterior walls.
• Seal drafts and keep interior temperatures above freezing.
• Open cabinet doors so warm room air can reach pipes under sinks.
• When temperatures drop well below freezing, let vulnerable faucets drip slowly so water keeps moving.

These steps address the cause: cold air around the pipe. Hot water may pass through the line for a moment, but if the pipe itself remains in a freezing environment, it can still freeze once the tap is shut off.

Is There Any Use for Hot Water?

Hot water does have a limited role. If a pipe has started to freeze but has not burst, gentle warmth can sometimes help clear the blockage. Guides usually recommend warm water on the outside of the pipe, heating pads, or warm towels. They do not recommend boiling water or open flames, which can stress or damage the pipe materials.

In other words, hot water is a careful tool for thawing, not a permanent winter strategy.

Why the Myth Persists Online

The hot water idea survives for a few reasons:

• It has a small grain of truth, so it feels believable.
• Short viral videos often reward simple statements and ignore the detailed context.
• People who try it once during a mild cold spell may get lucky and conclude that “it works,” then repeat the advice later.

When an extreme cold snap hits, that oversimplified advice can give a false sense of security, and homeowners may skip the more effective steps that actually protect pipes.

Better Ways to Prepare Before a Freeze

• Identify any plumbing that runs through unheated spaces and insulate those stretches.
• Disconnect garden hoses and shut off and drain outdoor spigots if possible.
• Know where the main shutoff is so water can be turned off quickly if a pipe does break.
• Use a slow drip from at-risk faucets only during the coldest periods, instead of running hot water heavily.

What To Do If a Pipe Freezes Anyway

If a faucet suddenly slows to a trickle during a freeze, that is a warning sign. The recommended response is:

• Turn on the tap slightly so thawing water has somewhere to go.
• Apply gentle, even heat to the suspected frozen section from the outside of the pipe.
• Avoid torches, open flames, or anything that can overheat or scorch the pipe.
• If the pipe has already burst, shut off water at the main valve and call a professional.

Bottom Line

Running hot water is not a cure-all and it is not a guaranteed way to stop frozen pipes. At best, it is a small part of a much bigger picture that includes insulation, airflow, indoor heat, and smart preparation. When social media clips promise that one hot water trick will solve every winter plumbing problem, it is safer to treat that as another seasonal myth.

Sources

• Atlas Butler: Common winter plumbing myths debunked
• WDSU: How to protect pipes from bursting in freezing weather
• Real Homes: How to thaw and prevent frozen pipes