How to Detect Water Leaks in Walls: 13 Steps (with Pictures) (2024)

Download Article

Explore this Article

parts

1Knowing When You Have a Leak in a Wall

2Pinpointing the Leak’s Location

How Can You Identify Where a Leak In Your House Is Coming From?

Other Sections

Tips and Warnings

Related Articles

References

Article Summary

Co-authored byDavid Balkan

Last Updated: June 13, 2024Fact Checked

Download Article

While many water leaks are caused by defective plumbing, leaks can also come from rainwater draining down inside the walls or from a cracked and leaky foundation. Long-term leaks can cause structural damage within your walls, and can also lead to serious mold problems in the walls. You can detect leaks in walls by looking for key signs of water damage, including peeling paint or wallpaper, or patches of discoloration. A musty smell indoors can also indicate a water leak. Pinpoint the exact location of a water leak by using a water meter or cutting into your walls.

Part 1

Part 1 of 2:

Knowing When You Have a Leak in a Wall

Download Article

  1. 1

    Look for standing puddles of water near a wall. This is the simplest way to tell that you have a water leak in your walls. You can be sure that water is leaking in a wall if you see conspicuously wet carpet or notice that the floor is always wet in a certain area of your home.

    • You’re most likely to see wet flooring near major appliances that use water (washing machine, dishwasher) or in the bathroom near the sink, toilet, or shower.
  2. 2

    Look for discoloration on a wall. If water is leaking in a wall, eventually the outer surface of the wall will take on some discoloration. Look for sections where the surface of the wall—whether it’s wallpapered, drywall, or even wood—is slightly washed out or has a lighter color than the surrounding area.

    • The shape of the discoloration is likely to be irregular.

    Advertisem*nt

  3. 3

    Inspect walls for a change in texture. Walls that have water leaks behind them are likely to develop a bubble-like texture. Paint or wallpaper will twist and buckle, forming rips or bubble-like shapes as the water distorts their usual texture.

    • Water-logged drywall will appear to sag downward. Small bubbles or drooping sections may also indicate the presence of water in your drywall.[1]
    • Walls with advanced leaks in them may also appear to curve outward. Drywall will eventually buckle under the weight of the water saturating it.
  4. 4

    Note any signs of mold or mildew. If a leak in a wall has gone on for some time, mold may be growing in and on your wall. In its early stages, mold looks like a dense cluster of black or brown dots. Even if you don’t see mold, it may still be growing inside of the walls that have been saturated with water by the leak.[2]

    • Mold can cause allergies, and lead to other potentially serious health problems. If you see mold growing on a wall, remove the mold and fix the leak in your wall.
  5. 5

    Pay attention to any musty smells. In cases where a leak behind a wall isn’t visible, you may be able to detect the leak using your sense of smell. Since water that leaks into walls never has a chance to dry out, the walls will begin to give off a humid, musty odor.

    • Musty-smelling walls will often be accompanied by other signs of a leak (e.g., discoloration). This will not always be the case though; sometimes an odor will be the only sign of a leak deep in a wall.
    • Thick drywall can effectively absorb water (almost like a sponge) and prevent any visual signs of the leak from showing.
  6. 6

    Listen for dripping sounds. Even if a water leak isn’t causing visible damage, you may still be able to detect the leak. Pay attention in the first few seconds after you turn off the shower, flush a toilet, or turn off a sink. If you hear a faint dripping sound coming from a nearby wall, it could be caused by a leaking pipe.[3]

    • Newer piping made of plastic PVC pipe will amplify the sound of dripping, making it easier to hear. If you have an older house with iron pipes, you’ll have a harder time hearing a leak.
  7. 7

    Keep an eye on your water bill. If a significant amount of water is leaking into your walls, it will increase the amount you pay on your monthly water bill. For example, the EPA suggests that a family of 4 typically uses no more than 12,000 gallons (45,000L) of water in cold months. If you’re using substantially more water and can’t figure out why, it could be because of a leak.[4]

    • Of course, this won’t tell you where the leak is located, but at least it can indicate whether or not you have a leak in a wall.
  8. 8

    Confirm whether the leak is coming from defective plumbing. Turn off all faucets and water-using appliances in your home, and write down the number on the water meter. Wait about 3 hours. Check the water meter again: if the amount of water used has increased, you’ll know that the leak is coming from indoor plumbing.[5]

    • If the water meter reading doesn’t change over the course of 3 hours, the leak isn’t coming from your plumbing. It may be coming from a leak in your roof or walls, or seeping in through basem*nt walls.
  9. 9

    Check for clogged eaves and downspouts. If your water leak isn’t coming from the plumbing, it may be that your eaves or downspouts are clogged. Excess rainwater (or snowmelt) with no downspout to flow through will eventually seep through your roof and walls, resulting in leaks. If you notice that eaves or downspouts are clogged, remove the clogging material (pine needles, leaves, etc.) and restore the flow of water.[6]

    • Even if you don’t notice water leaks in your walls, check your eaves and downspouts annually to make sure they’re not clogged.
  10. 10

    Check for leaks in foundation walls. Given the right conditions, water can seep into your house through the foundation walls. These leaks are seldom caused by faulty plumbing. Foundation walls crack and leak when water soaks into the walls and eventually begins to drain inside of your basem*nt. Leaks in foundation walls are usually fixed in 1 of 2 ways:[7]

    • Externally, by digging a trench around the foundation and sealing the entire underground portion of the foundation with sealant and a protective barrier.
    • Internally, by removing any damaged studs and drywall and patching the crack up with epoxy.
  11. Advertisem*nt

Part 2

Part 2 of 2:

Pinpointing the Leak’s Location

Download Article

  1. 1

    Scan for moisture inside walls with a moisture meter. A moisture meter is a piece of equipment which, when placed directly against a wall, will analyze the moisture content of that wall. If you know that you have a leak within a certain wall, but are unaware of the precise location, place the moisture meter at 5 or 6 different spots on the wall. Whichever spot gives the highest moisture reading is closest to the leak.[8]

    • You can purchase or rent a moisture meter at a large hardware store or home-improvement store. These gadgets are frequently used by professional home-inspectors to find leaks or wet walls.
  2. 2

    Find the cold, leaky part of a wall with an infrared camera. Infrared cameras detect heat, and can indicate the temperature of a wall. A leaky, wet wall will have a cooler temperature than the surrounding wall. Train an infrared camera on a wall with a leak, and look to see which section of the wall is the coldest. This will be the section of the wall nearest the leak.[9]

    • When using an infrared camera, hot objects will have red or orange coloring, while cool objects will have blue or purple coloring.
    • You may be able to rent an infrared camera from a professional contractor, a home-improvement center, or from a photography shop.
  3. 3

    Cut into your drywall to find the source of a leak. Use a utility knife to score a line about 10 inches (25cm) long into your drywall at the location where you see visible signs of a water leak (mold, discolored drywall, etc.). Then, using a drywall saw, cut along the line you just scored. Cut a hole in the wall large enough for your head to fit inside. Stick your head in the wall and look around until you spot the source of your leak.[10] Enlarge the hole so that you can also insert a flashlight to see better inside the wall, if needed.

    • Often, the patch of wall which shows signs of a leak is not directly in front of the leaky pipe or fixture. Water can drain along the outside of pipes in your walls or trickle many feet down the inside of your walls before the telltale signs of a leak become visible.
    • Both a utility knife and a drywall saw can be purchased at your local hardware store.
  4. Advertisem*nt

How Can You Identify Where a Leak In Your House Is Coming From?

Expert Q&A

Search

Add New Question

  • Question

    Is there a tool to detect water leaks?

    David Balkan
    Professional Plumber

    David Balkan is a Professional Plumber, CEO of Balkan Sewer and Water Main Service, and President of Balkan Sewer and Drain Cleaning. As a hands-on owner of these companies for over 40 years, David is knowledgeable about water service lines, sewers, and drain line issues. David is a Committee Chairman of the Master Plumbers Council and has sat on the Executive Committee of the Sub Surface Plumbers Association of New York for over 30 years. His knowledge and solution-oriented approach contributed to Balkan Sewer and Water Main Service being the largest and most trusted service in New York City and the recipient of the 2017 Angie’s List Super Service Award.

    David Balkan

    Professional Plumber

    Expert Answer

    Your water meter is your best bet. Turn off any running water in your home, like the toilets, and check to see if the meter is moving. If it is, you have an interior leak.

    Thanks! We're glad this was helpful.
    Thank you for your feedback.
    If wikiHow has helped you, please consider a small contribution to support us in helping more readers like you. We’re committed to providing the world with free how-to resources, and even $1 helps us in our mission.Support wikiHow

    YesNo

    Not Helpful 21Helpful 28

Ask a Question

200 characters left

Include your email address to get a message when this question is answered.

Submit

      Advertisem*nt

      Tips

      • If you suspect that you have a leak in a wall but can’t pinpoint the exact location, call a local plumber or a professional home inspector to check out the leak.[11]

        Thanks

        Helpful0Not Helpful0

      • Once the leak is plugged, you should fix the peeling paint on the ceiling or wall.

        Thanks

        Helpful4Not Helpful3

      Submit a Tip

      All tip submissions are carefully reviewed before being published

      Submit

      Thanks for submitting a tip for review!

      Advertisem*nt

      You Might Also Like

      How to Adjust a Pressure Switch8 Easy Ways to Repair a Leaky Pipe
      How to Calculate and Measure Water Pump HorsepowerHow to Check Your Water Quality with or without a KitHow toPrime a Water PumpHow toRaise the pH of WaterHow toTurn Water Back onHow toBoil WaterHow to Chug Water Safely: Tips and TricksHow to Increase Water PressureHow toTroubleshoot Low Water PressureHow toFind a Leak in Your Swimming PoolHow toRemove Calcium from WaterHow toSoften Hard Water

      Advertisem*nt

      More References (2)

      About This Article

      How to Detect Water Leaks in Walls: 13 Steps (with Pictures) (34)

      Co-authored by:

      David Balkan

      Professional Plumber

      This article was co-authored by David Balkan. David Balkan is a Professional Plumber, CEO of Balkan Sewer and Water Main Service, and President of Balkan Sewer and Drain Cleaning. As a hands-on owner of these companies for over 40 years, David is knowledgeable about water service lines, sewers, and drain line issues. David is a Committee Chairman of the Master Plumbers Council and has sat on the Executive Committee of the Sub Surface Plumbers Association of New York for over 30 years. His knowledge and solution-oriented approach contributed to Balkan Sewer and Water Main Service being the largest and most trusted service in New York City and the recipient of the 2017 Angie’s List Super Service Award. This article has been viewed 455,565 times.

      96 votes - 86%

      Co-authors: 12

      Updated: June 13, 2024

      Views:455,565

      Categories: Water

      Article SummaryX

      To detect a water leak in your wall, watch for standing puddles of water near your walls or near major appliances that use water, like your washing machine. Additionally, check to see if your walls have any discolored spots or bubbles, which may mean there’s been water damage. If the leak’s been going on for some time, there may even be clusters of black or brown mold dots on the wall or ceiling. Besides wall damage, you may be able to hear dripping coming from inside the wall. If you notice any of these signs, try using a moisture meter, which can be bought at your local hardware store. To use it, scan the device over the wall to find the area that has the highest moisture reading, which will be where the leak is coming from. To learn how to cut into your drywall to find the source of the leak, read on.

      Did this summary help you?

      In other languages

      Portuguese

      Spanish

      German

      French

      Arabic

      Thai

      Indonesian

      Dutch

      Hindi

      Russian

      Korean

      Turkish

      • Print
      • Send fan mail to authors

      Thanks to all authors for creating a page that has been read 455,565 times.

      Reader Success Stories

      • How to Detect Water Leaks in Walls: 13 Steps (with Pictures) (35)

        Sudhir H.

        Sep 10, 2019

        "Exhaustive information provided in an easy-to-understand manner."

      Did this article help you?

      Advertisem*nt

      How to Detect Water Leaks in Walls: 13 Steps (with Pictures) (2024)
      Top Articles
      Latest Posts
      Article information

      Author: Ray Christiansen

      Last Updated:

      Views: 6123

      Rating: 4.9 / 5 (49 voted)

      Reviews: 80% of readers found this page helpful

      Author information

      Name: Ray Christiansen

      Birthday: 1998-05-04

      Address: Apt. 814 34339 Sauer Islands, Hirtheville, GA 02446-8771

      Phone: +337636892828

      Job: Lead Hospitality Designer

      Hobby: Urban exploration, Tai chi, Lockpicking, Fashion, Gunsmithing, Pottery, Geocaching

      Introduction: My name is Ray Christiansen, I am a fair, good, cute, gentle, vast, glamorous, excited person who loves writing and wants to share my knowledge and understanding with you.