Detecting A Leak In Your Plumbing System

Plumbing leaks aren't always obvious. Some show up as a puddle under the sink. Others hide behind walls, under floors, or outside, quietly wasting water and causing damage until they turn into a much bigger headache. If you suspect a leak, the goal is simple: confirm it quickly, narrow down where it's coming from, and take the right next step.

Start with the easiest red flags:

• A sudden spike in your water bill (with no change in usage)

• Damp spots, bubbling paint, or "mysterious" water stains

• You hear water running when nothing is on

• Musty smells that don't go away

• Mold showing up around baseboards or cabinets

• Warm or damp patches on floors (especially near bathrooms or kitchens)

If you're seeing active water spreading, skip the checklist and shut off the water first.

One of the most reliable ways to confirm a hidden leak is to test for water usage when everything is off.

How to do it:

1. Turn off everything that uses water (faucets, dishwasher, washing machine, irrigation).

2. Record your water meter reading, or take a photo.

3. Wait (15-20 minutes works for a quick check; longer can help if it's intermittent).

4. Check the meter again. If it moved, water is being used somewhere.

Pro Tip: Many meters have a small triangle/star "leak indicator." If it spins when everything is off, that's a strong sign you have a leak.

Toilets are one of the most common "silent" leaks because they can leak from tank to bowl without any obvious overflow.

Quick dye test:

1. Add a dye tablet or a few drops of food coloring to the toilet tank.

2. Don't flush, wait 5-10 minutes.

3. If color shows up in the bowl, the toilet is leaking.

This is an easy fix in many cases, but it's also an easy one to miss, so it's worth checking.

If the meter test suggests a leak, these are the first places to look:

• Under sinks (supply lines, shut-off valves, drain traps)

• Behind toilets (shut-off valve and supply line)

• Around the water heater (valve connections and drain area)

• Dishwasher and fridge water line connections

• Laundry area (washer hoses and valves)

Look for moisture, mineral staining, warped cabinet bottoms, or a slow drip that only happens occasionally.

Some of the most expensive "mystery" water bills come from outdoor leaks:

• Hose bibs that drip when turned off

• Irrigation lines and sprinkler heads

• Cracked outdoor supply lines (especially after freezing temps)

If your home has irrigation on a separate line, make sure your test accounts for that.

Our licensed technicians at Proto Home Service specialize in professional leak detection, leak repairs and plumbing repiping.

Call us today at (617) 842-9104 or schedule online to keep your home leak free!