How to Prevent Frozen Pipes
Boston and South Shore

Frozen pipes can turn one cold night into a major plumbing emergency. Homes across Boston, Greater Boston, and the South Shore are especially vulnerable where water lines run through older exterior walls, unfinished basements, garages, crawl spaces, or additions with limited insulation. The good news is that a few practical checks before the next hard freeze can lower the risk and help you respond safely if water flow suddenly stops.

When water freezes inside a pipe, it expands and creates pressure between the ice blockage and a closed faucet. The pipe may split, but the damage often stays hidden until the ice thaws and water begins flowing again. That is why a frozen line can appear manageable at first and then release water into a wall, ceiling, or basement.

The Massachusetts Division of Insurance reported in January 2026 that 48.6 percent of the state’s 2024 homeowners insurance claims involved non-flood water losses and freezing-related damage. The agency also warned that coverage for a burst pipe can depend on whether the home was properly heated and maintained. Homeowners should review their own policy rather than assume every loss is covered.

Start with supply lines in unheated or drafty spaces. Common trouble spots include pipes along exterior walls, under sinks, near basement rim joists, in crawl spaces, above garages, and close to where the water service enters the foundation. Outdoor hose connections and lines serving seasonal fixtures also need attention.

A pipe does not need to be in a completely unheated room to freeze. A small opening around a sill, utility penetration, or foundation can direct cold air onto one section of pipe. Seal obvious gaps with a material suited to the location, and add pipe insulation where lines remain exposed. If a pipe repeatedly freezes, ask a licensed plumber whether rerouting it or improving protection around it is the safer long-term fix.

• Disconnect and drain garden hoses. If your home has an interior shutoff for an outdoor faucet, close it and drain the exterior line.
• Insulate accessible hot and cold water lines in basements, crawl spaces, garages, and other cold areas.
• Keep garage doors closed when plumbing runs through the garage, and keep warm air circulating around pipes under sinks during severe cold.
• Know where the main water shutoff is and make sure an adult in the home can operate it.
• If you will be away, keep the heat on. For a seasonal or vacant property, arrange a professional winterization plan instead of guessing which lines need to be drained.

During an extreme cold snap, a small trickle from the faucet served by an exposed line may help keep water moving. This is a short-term precaution for a known vulnerable pipe, not a substitute for insulation, air sealing, or repair.

A faucet that produces only a trickle, despite normal flow elsewhere, can point to a frozen section. First, check the area for bulging, cracking, or active leakage. If you see water, shut off the main supply and call for plumbing service.

If the suspected frozen section is exposed, intact, and safe to reach, leave the faucet open and warm the pipe gradually with a hair dryer or towels soaked in hot water. Start near the faucet and work toward the colder section. Never use a torch, propane heater, or other open flame. Massachusetts emergency guidance specifically warns against open-flame thawing.

Stop and call a licensed plumber if the frozen area is inside a wall, you cannot locate it, the pipe is damaged, or normal pressure does not return. Check other faucets too, because more than one line may be affected.

Fast action matters when a pipe freezes or bursts. Proto Home Service provides plumbing repair and 24/7 emergency service across Boston, Greater Boston, and the South Shore. We can locate the affected section, repair damaged piping, and help identify why that area froze so the problem is less likely to return. If you have reduced water flow, visible leaking, or concerns about exposed piping before the next cold snap, call 617-842-9104 or request service online.