When pipes freeze during cold weather, immediate action is required to prevent bursting and water damage. The first critical step is shutting off the main water supply to stop additional water from entering the system, then opening affected faucets to relieve pressure buildup. Safe thawing methods include applying gradual heat using hair dryers, heating pads, or space heaters—never open flames—while monitoring for leaks. For drain pipes, boiling salt water (1 cup salt per 1.5L water) poured down the drain can help dissolve ice blockages. Hidden or inaccessible frozen pipes often require professional equipment like thaw machines, and plumbers should be contacted if DIY methods fail or if pipes are located behind walls. Prevention remains key: insulating exposed pipes, sealing drafts, maintaining indoor temperatures above 55°F, and allowing faucets to drip during extreme cold can reduce risks.

• Immediate actions: Shut off water main, open faucets, apply heat gradually to frozen sections [index:Source3][index:Source7][index:Source8]
• DIY solutions: Use hair dryers, heating pads, or boiling salt water for drains (1 cup salt:1.5L water) [index:Source2][index:Source5][index:Source6]
• Professional help needed: For pipes behind walls, burst pipes, or if thawing fails after 45 minutes [index:Source1][index:Source5][index:Source8]
• Prevention tips: Insulate pipes, seal cracks, maintain 55°F+ indoors, let faucets drip [index:Source3][index:Source6][index:Source7]

Handling Frozen Pipes: Step-by-Step Solutions and Safety Measures

Emergency Response: First Steps When Pipes Freeze

The moment you suspect frozen pipes—indicated by reduced water flow, frost on exposed pipes, or unusual noises—act quickly to minimize damage. Water expands as it freezes, creating pressure that can crack or burst pipes, even if the ice hasn’t fully blocked the line. The American Red Cross emphasizes that bursts often occur when thawing begins, as melted ice rushes through cracks [index:Source6]. Follow these verified steps to mitigate risks:

• Shut off the main water supply immediately to prevent additional water from freezing and increasing pressure. The valve is typically located where the main line enters the home, often in basements or crawl spaces [index:Source7][index:Source8]. Roto-Rooter advises tagging this valve with your plumber’s contact for emergencies [index:Source9].
• Open all faucets connected to the frozen pipe, including hot and cold handles. This relieves pressure in the system and allows melting water to escape, reducing burst risks [index:Source3][index:Source8]. Nationwide recommends keeping faucets running during thawing to help melt ice [index:Source3].
• Locate the frozen section by checking for frost accumulation, bulging pipes, or areas where water flow stops abruptly. Exposed pipes in basements, attics, or under sinks are common freeze points [index:Source1][index:Source4]. The Handyman notes that drafty foundations or uninsulated walls often hide frozen spots [index:Source4].
• Inspect for leaks or cracks before thawing. If you see water stains, dampness, or hear hissing sounds, the pipe may already be damaged. In such cases, turn off the water and call a plumber immediately [index:Source1][index:Source7].

Avoid using open flames (e.g., blowtorches or propane heaters) to thaw pipes, as these can damage pipes, start fires, or release toxic fumes from solder [index:Source6][index:Source8]. Mr. Rooter Plumbing warns that improper thawing is a leading cause of pipe bursts during winter [index:Source8].

Safe Thawing Methods and When to Call a Professional

Once you’ve secured the water supply and opened faucets, apply heat to the frozen section using only approved methods. The thawing process typically takes 30–45 minutes, but complex blockages may require longer [index:Source3]. Use these techniques based on pipe location and accessibility:

• For exposed pipes:
• Wrap the pipe in electric heating pads or towels soaked in hot water (not boiling). Replace towels as they cool [index:Source6].
• Use a hairdryer on low heat, moving it back and forth along the pipe. Keep the dryer at least 6 inches away to avoid overheating one spot [index:Source3][index:Source8].
• Position a portable space heater near the pipe, ensuring it’s at least 3 feet away from flammable materials. Never leave heaters unattended [index:Source6][index:Source4].
• For drain pipes:
• Pour boiling salt water (1 cup salt per 1.5 liters of water) down the drain to melt ice. A Reddit user reported success with this method for backed-up drains [index:Source2].
• Repeat every 10–15 minutes until water flows freely. Avoid chemical drain cleaners, as they can corrode pipes [index:Source5].
• For pipes behind walls or underground:
• Do not attempt DIY thawing if the pipe isn’t visible. Blind & Sons and Buildium warn that hidden pipes require professional thaw machines to avoid damaging drywall or electrical systems [index:Source1][index:Source5].
• Plumbers use infrared cameras to locate frozen sections and thaw machines that send controlled electric currents through the pipe [index:Source5][index:Source8].

Call a plumber immediately if:

• The pipe doesn’t thaw after 45 minutes of safe heating [index:Source3].
• You suspect the pipe is behind a wall, ceiling, or underground [index:Source1][index:Source5].
• Water leaks or bursts are visible. Roto-Rooter notes that burst pipes can release hundreds of gallons per hour, causing severe flooding [index:Source7].
• The frozen pipe supplies your main water line or multiple fixtures [index:Source8].

Professional thawing typically costs $150–$500, while burst pipe repairs can exceed $1,000 depending on water damage [index:Source9]. Angi recommends having a plumber’s contact saved before winter, as emergency calls spike during cold snaps [index:Source9][index:Source10].