Signs You Have a Water Leak in Your Home — And What to Do About It

Water leaks are sneaky.

Sometimes they're obvious.

There's water pouring out of a broken pipe and suddenly your entire household becomes a professional plumbing emergency response team.

Other leaks are much quieter.

A pipe behind a wall can leak slowly for weeks.

A toilet can continuously waste water without making much noise.

A hidden pipe underneath a foundation can develop a problem that you don't discover until your water bill starts behaving strangely.

The earlier you catch a leak, the better.

Here's what to watch for.

1. Your water bill suddenly increases

This is one of the easiest signs to overlook.

If your household hasn't changed its water habits but your bill suddenly jumps, investigate.

Maybe you've been watering the lawn more.

Maybe guests have been staying over.

Maybe there's another explanation.

But an unexplained increase can be a sign that water is going somewhere it shouldn't.

A small leak can waste a surprising amount of water over time.

2. Your water meter is still moving

You can perform a simple check.

Make sure everyone in the house has stopped using water.

Turn off faucets.

Don't run the washing machine.

Don't flush toilets.

Don't run the dishwasher.

Then check your water meter.

If the meter continues showing water usage while everything is off, you may have a leak.

Different meters work differently, so the exact test will depend on your setup.

But the basic idea is simple:

If nobody is using water and your system appears to be using water, something deserves investigation.

3. You hear running water

Listen to your house.

Not in a creepy "is the house talking?" sort of way.

Just pay attention.

Do you hear:

• Running water?
• Dripping?
• Hissing?
• Water moving through pipes?

If everything is turned off but you can still hear water, don't automatically ignore it.

Some sounds are completely normal.

Others aren't.

If the sound is new or persistent, have it checked.

4. Your toilet keeps running

A toilet that continues running after you flush might not seem like a major problem.

But if it happens constantly, you're wasting water.

The cause could be something relatively simple, such as a faulty flapper, fill valve or another component inside the tank.

Sometimes you can fix these parts yourself.

If you've tried and the toilet continues running, call a plumber.

5. Damp spots appear on walls

A damp patch on the wall is not something to decorate around.

Water stains may appear as:

• Yellowing
• Brown spots
• Discoloration
• Bubbling paint
• Peeling wallpaper
• Soft drywall

The tricky part is that the visible stain isn't necessarily directly beneath the leak.

Water can travel.

A pipe could be leaking several feet away from where the stain appears.

6. Your ceiling develops a stain

Ceiling stains deserve particular attention.

A water stain may indicate plumbing above the ceiling, a roof problem or another source of moisture.

Don't automatically assume it's plumbing.

But don't ignore it either.

If the stain is growing, the ceiling feels soft or you notice active dripping, deal with it promptly.

7. Your house smells musty

A persistent musty smell can indicate moisture.

Again, it doesn't automatically mean a plumbing leak.

Humidity, ventilation problems, condensation and other issues can produce similar smells.

But if the smell is concentrated around bathrooms, kitchens, walls, floors or plumbing areas, investigate.

8. Mold or mildew keeps appearing

Mold and mildew need moisture.

If you repeatedly clean an area only to have the problem return, ask where the moisture is coming from.

A plumbing leak could be one possible source.

This is especially important if the affected area isn't somewhere you'd expect normal moisture.

9. Your floor feels damp

A damp floor around a toilet or under a sink is easier to understand.

But unexplained moisture elsewhere is different.

If flooring becomes damp without an obvious source, don't simply dry it and wait.

Investigate.

Water beneath flooring can cause damage over time.

10. You notice unusually warm flooring

This can sometimes be an important clue.

If a hot-water line beneath a floor develops a leak, the surrounding area may feel warmer than expected.

You might notice a warm spot even when the rest of the floor feels normal.

This doesn't prove you have a hidden leak, but it's a good reason to investigate.

11. Your water pressure changes

Sudden changes in water pressure can have several causes.

It could be:

• A plumbing leak
• Mineral buildup
• A clogged fixture
• A pressure regulator problem
• Municipal supply changes

If your water pressure suddenly changes throughout the house, don't assume it's simply "one of those things."

Find out why.

12. Doors or floors seem to change

Moisture can affect building materials.

You might notice:

• Warped flooring
• Swollen wood
• Doors sticking
• Buckling
• Changes around baseboards

Again, these symptoms have many possible causes.

But unexplained changes combined with other leak symptoms deserve attention.

What should you do when you suspect a leak?

First, locate the source if you can safely do so.

If water is actively leaking from a fixture and you know the local shutoff, close it.

If the situation is more serious, you may need to shut off the home's main water supply.

This is why every homeowner should know where the main shutoff is before they need it.

Don't assume the leak will fix itself

Water leaks generally don't become less problematic by being ignored.

A tiny leak today can become:

• Water damage
• Mold growth
• Damaged flooring
• Damaged drywall
• Structural problems
• Higher water bills
• A much larger repair

The sooner you identify the source, the more options you may have.

When should you call a plumber?

Call a professional if:

• You can't find the source
• The leak is behind a wall
• Water is entering the ceiling
• Multiple fixtures are affected
• Your water meter indicates unexplained usage
• The leak is beneath the foundation
• You have sewage backup
• A pipe has burst
• The problem keeps returning

A professional may use leak-detection equipment that allows them to locate the source without immediately tearing apart your house.

And that can be a very good thing.