How to Prevent Frozen Pipes in Older Chester County Homes

To prevent frozen pipes, find the lines that run through cold spaces (exterior walls, crawl spaces, garages and unheated porches), insulate or heat them, shut off and drain outdoor faucets before the first hard freeze, and keep the house at 55°F or warmer, even when you travel. On the coldest nights, let vulnerable faucets drip.

By West Chester Flood Cleanup Editorial Team · Published 2026-11-05

Older homes around West Chester, Downingtown and the rest of Chester County were built long before modern insulation codes. Many have been added onto more than once, which leaves plumbing in odd, cold places. A little work in November can prevent a burst pipe in January.

Where pipes freeze in stone and frame homes

Water pipes freeze where cold outside air reaches them and heat from the house doesn't. In older local homes, the usual trouble spots are:

• Exterior walls of kitchens and baths. Sinks were often placed under windows on outside walls. Supply lines run through a wall cavity with little or no insulation behind the cabinet.
• Additions over crawl spaces. A kitchen or family-room addition built on piers or a block crawl space is often the coldest part of the house. Vents, gaps around the rim joist and missing insulation let freezing air in.
• Stone foundation walls. Fieldstone and rubble walls conduct cold. A pipe strapped tight to the wall of a cellar can freeze even when the room feels fine, especially near a cellar window or the old coal chute.
• Garages and porches. Lines to a laundry in the garage, or pipes running through an enclosed porch, often sit in unheated space.
• Attic and second-floor baths. Converted attics and dormer baths can have pipes in knee walls that sit next to cold roof space.
• Where the service line enters. The main line comes through the foundation. Gaps around it let cold air blow right onto the pipe.

Frame houses from the 1950s to the 1970s have their own weak points: cantilevered floors, bump-outs and plumbing walls that back onto a garage.

Pre-winter checklist

Do this before the first stretch of nights in the teens. Cold snaps here can arrive quickly once winter sets in.

1. Walk the basement and crawl space with a flashlight. Look for pipes near vents, windows, the rim joist and outside walls. Note any line you can see daylight or feel a draft near.
2. Insulate exposed pipes. Foam pipe sleeves from any hardware store fit most copper and PEX lines. Tape the seams. Pay attention to elbows and valves.
3. Seal air leaks. Use expanding foam around the main water line where it enters, along the rim joist and around dryer vents. Close crawl-space vents for winter if your house was built with operable vents.
4. Consider heat cable on problem runs. For a pipe that has frozen before, a UL-listed, self-regulating heat cable installed to the maker's instructions can help. Never wrap cable over itself, and plug it into a GFCI outlet.
5. Know your main shutoff. Make sure everyone in the house knows where it is and that it turns. A stuck valve is worth replacing before winter.
6. Service the heating system. A furnace or boiler that fails on a cold night is a common cause of frozen pipes.
7. Open sink cabinets on outside walls on the coldest nights so warm room air reaches the pipes.

Hose bibs and sprinkler lines

Outdoor faucets are the most common freeze point we see, because they're where water and outside air meet.

• Close the inside shutoff for each outdoor faucet. It's usually a small valve on the basement ceiling just inside the wall where the faucet comes out.
• Open the outdoor faucet and leave it open so trapped water can drain. If the inside valve has a small drain cap, open it over a bucket.
• Disconnect hoses. A hose left on traps water in the faucet, even a frost-free one, and can split the pipe inside the wall. You may not see that leak until spring, when you first turn the water back on.
• Irrigation systems need to be shut off and blown out with compressed air. If you didn't install the system, follow the installer's instructions or hire them to winterize it.

Leaving for the holidays

An empty house in a cold snap is the classic setup for a burst pipe. Nobody is there to notice the heat went out, and water can run for days.

• Keep the thermostat at 55°F or higher. Don't turn it down further to save money.
• Shut off the main water if you'll be gone more than a day or two, and open a faucet to drain pressure. If you have a hot-water boiler or a fire sprinkler system, ask your service company first, because some systems need water supply.
• Ask someone to check the house every day or two during a deep freeze.
• Use a smart thermostat or a low-cost temperature and leak sensor that alerts your phone.
• Check your policy. Many homeowners policies expect you to keep heat on or drain the system when the home is vacant. Ask your agent what counts as reasonable care.

Signs a pipe has frozen

Catching a frozen pipe before it splits saves a lot of trouble.

• A faucet gives only a trickle, or nothing at all, on a cold morning
• Frost on a visible pipe, or a pipe that feels very cold and stiff
• A toilet that won't refill
• Strange smells from a drain (the trapped air has nowhere to go)
• A bulge or a hairline split in an exposed pipe

If one fixture on an outside wall stops working, the frozen section is usually in that wall or the floor beneath it.

Thawing it safely

1. Keep the faucet open. As ice melts, flowing water helps melt the rest and relieves pressure.
2. Apply gentle heat working from the faucet back toward the frozen section: a hair dryer, a space heater kept at a safe distance, or warm towels.
3. Never use an open flame. Propane torches and heat guns start house fires and can melt PEX or solder joints.
4. Check for leaks as it thaws. A pipe that split while frozen often won't leak until the ice melts. Have someone stand by the main shutoff.
5. Call a plumber if you can't find or reach the frozen section, or if more than one fixture is out.

If the pipe has already split and water is coming out, turn off the main and follow our burst pipe first-hour guide.

When a frozen pipe does burst

A burst inside a wall or ceiling is a water damage job, not just a plumbing job. The plumber repairs the line. Then wet drywall, insulation, subfloor and plaster need to be found with moisture meters and dried before mold can start. Our water damage restoration team handles that drying and documents it for your insurer. We cover homes throughout the borough. See our West Chester page for local details.

FAQ

At what temperature do pipes freeze?

There's no single number. Pipes in unprotected spaces are at risk once outdoor temperatures stay in the low 20s or below for several hours, especially with wind. Pipes in insulated, heated spaces rarely freeze.

Does dripping a faucet really help?

Yes, on the coldest nights. A slow drip keeps water moving and relieves pressure between the ice and the faucet, which is what usually splits the pipe. Drip both hot and cold on fixtures along outside walls.

Are PEX pipes freeze-proof?

No. PEX tolerates freezing better than copper because it can stretch a little, but fittings can still fail and the pipe can split. Insulate it the same way.

Should I close crawl-space vents in winter?

If your crawl space was built with operable vents, closing them in winter helps keep pipes warmer. Many building pros now recommend sealed, conditioned crawl spaces. Ask a contractor before making permanent changes.

Worried about pipes this winter?

If a line has already burst, call (555) 000-0000 and we'll start drying right away. (555) 000-0000 · Get a Free Quote