Leak Detection & Pipe Repair in Boston

Check for a leak yourself with the water meter

The simplest leak test uses the water meter, which in most Boston-area homes is in the basement where the water line enters. Make sure nothing in the house is using water, then watch the meter. If it moves, or its small leak-indicator dial turns, water is going somewhere. Then narrow it down.

1. Turn off every faucet, appliance and the irrigation system, and make sure no one runs water.
2. Look at the meter's dial or low-flow indicator and note the reading. Wait 15 to 30 minutes and check again.
3. If it has moved, shut the valves under each toilet and test again. If the movement stops, a toilet is leaking (see below).
4. Put a few drops of food coloring in each toilet tank; color in the bowl after 15 minutes without flushing means a leaking flapper.
5. If the meter still moves with all fixtures off, the leak is in the pipes, possibly in a wall, under a floor or in the service line outside. That's a job for a plumber.

How plumbers find leaks without opening every wall

Leak detection is about narrowing the search before cutting anything. A plumber usually starts by isolating parts of the system with valves and a pressure test, which tells them whether the leak is on the hot or cold side, inside the house or on the service line. Then they use tools to pinpoint it: acoustic listening equipment that picks up the sound of escaping water, thermal cameras that show the cool or warm patch a leak makes in a wall or floor, and moisture meters that confirm where materials are wet.

The result should be one small, targeted opening instead of a wall full of holes. Ask the plumber how they plan to find the leak and how much opening up they expect, and who repairs the drywall or ceiling afterwards (plumbers usually don't).

Water coming from the unit above

In Boston's triple-deckers, row houses and condo buildings, the most alarming leaks come from someone else's plumbing: a drip through the bathroom ceiling, a stain spreading from the kitchen light. Knock on the door upstairs or call the building manager first. The usual culprits are an overflowing tub or toilet, a failed washing machine hose, a leaking shower valve or a cracked drain line inside the floor between units. If no one answers and the water keeps coming, the building's main shutoff will stop it, which is why every unit owner should know where that valve is.

Who pays depends on where the leak is and on your condo documents or lease: as a rule the unit owner is responsible for pipes and fixtures serving only their unit, and the association for common pipes such as shared drain stacks. Photograph the damage, note the time, and tell your insurer early. A plumber can confirm the source, which is the fact everyone's insurance company will want to know.

Old pipes in Boston houses: galvanized steel, lead and early copper

Many older Boston-area homes still have some galvanized steel water pipe, installed for decades before copper took over. Galvanized pipe corrodes from the inside, which narrows the pipe (low pressure, rusty water) and eventually rusts through, usually at the threaded joints. Once one section starts leaking, others aren't far behind, and repiping the house in copper or PEX is often cheaper over a few years than chasing leaks one at a time.

The pipe that brings water from the street into the house, the service line, can be lead in older homes. Lead service lines are a health issue rather than a leak issue, and Boston and many nearby towns run programs to replace them. Our lead pipes guide explains how to check yours and what the programs offer.

Signs that the supply pipes themselves are the problem, rather than one fixture: pressure that has dropped gradually over the years, especially on upper floors; rusty or brown water from the hot and cold taps after the water has been off; pinhole leaks that keep appearing in different places; and visible corrosion or white crust at threaded joints in the basement. One of those alone may be a local fault. Several together usually mean the pipe is near the end of its life, and that is the moment to ask a plumber to price a partial or whole-house repipe rather than another patch.

Toilet and fixture leaks: the cheap ones to fix

The most common invisible leak is a toilet. A worn flapper lets water trickle from the tank into the bowl all day, and you may hear the tank refill now and then for no reason. It can waste a lot of water but is one of the cheapest fixes in plumbing. Dripping faucets, leaking shower valves and supply lines under sinks are the next most common, and all are quick repairs when caught early. Massachusetts lets you repair a leak in a faucet or valve without a permit, but replacing a faucet, a fixture or any piping is permit work for a licensed plumber.

Washing machine hoses deserve a mention: rubber hoses burst with age and can flood a floor quickly. Replacing them with braided stainless steel hoses is a cheap insurance policy, especially in a triple-decker or condo with neighbors below.

What leak detection and pipe repair cost

Leak detection is usually priced by the visit or the hour, and the repair separately, so ask for both. Fixing a single accessible leak is a modest job; repiping a whole house is a major one, priced by the size of the house and how many walls must be opened. Published leak-detection prices mostly come from slab-leak pages written for warmer states; ConsumerAffairs notes that slab leaks are not common in Boston, so treat them as a rough guide.

One Boston-specific option: if the leak is in the private water service pipe outside the house, BWSC's Leak Up To Owner program will repair private-side service leaks for one- to three-family homes with a service of 2 inches or less, and let the owner pay over 24 installments on the water bill. Call BWSC Operations at (617) 989-7900 to ask.