How To Detect Water Leaks In Walls: 13 Steps (with Pictures) - WikiHow

Skip to ContentQuizzes
  • Home
  • Random
  • Browse Articles
  • Quizzes & Games
  • All QuizzesHot
  • Love Quizzes
  • Personality Quizzes
  • Fun Games
  • Dating Simulator
  • Learn Something New
  • Forums
  • Courses
  • Happiness Hub
  • Explore More
  • Support wikiHow
  • About wikiHow
  • Log in / Sign up
Terms of Use wikiHow is where trusted research and expert knowledge come together. Learn why people trust wikiHow How to Detect Water Leaks in Walls PDF download Download Article Explore this Article parts 1 Identifying a Leak in a Wall 2 Pinpointing the Leak’s Location How do you identify the source of a leak in your house? Other Sections Expert Q&A Video Tips and Warnings Related Articles References Article Summary Co-authored by David Balkan

Last Updated: July 9, 2025 Fact Checked

PDF download Download Article X

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. There are 7 references cited in this article, which can be found at the bottom of the page. This article has been fact-checked, ensuring the accuracy of any cited facts and confirming the authority of its sources. This article has been viewed 490,073 times.

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.

Steps

Part 1 Part 1 of 2:

Identifying a Leak in a Wall

PDF download Download Article
  1. Step 1 Look for standing puddles of water near a wall. 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 a 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. Step 2 Look for discoloration on a wall. 2 Look for discoloration on a wall. If water is leaking into 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.
    Advertisement
  3. Step 3 Inspect walls for a change in texture. 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. The drywall will eventually buckle under the weight of the water saturating it.
  4. Step 4 Note any signs of mold or mildew. 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 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.[3]
  5. Step 5 Pay attention to any musty smells. 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 the water that leaks into walls never has a chance to dry out, the walls will begin to give off a humid, musty odor.[4]
    • 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. Step 6 Listen for dripping sounds. 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.[5]
    • 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. Step 7 Keep an eye on your water bill. 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 (45,000 L) 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.[6]
    • Of course, this won’t tell you where the leak is located, but at least it can indicate whether or not you leak into a wall.
  8. Step 8 Confirm whether the leak is coming from defective plumbing. 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.[7]
    • If the water meter reading doesn’t change over 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 basement walls.
  9. Step 9 Check for clogged eaves and downspouts. 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.
    • 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. Step 10 Check for leaks in the foundation walls. 10 Check for leaks in the 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 your basement. Leaks in foundation walls are usually fixed in 1 of 2 ways:[8]
    • 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. Advertisement
Part 2 Part 2 of 2:

Pinpointing the Leak’s Location

PDF download Download Article
  1. Step 1 Scan for moisture inside walls with a moisture meter. 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 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.[9]
    • 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. Step 2 Find the cold, leaky part of a wall with an infrared camera. 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.
    • 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 a photography shop.
  3. Step 3 Cut into your drywall to find the source of a leak. 3 Cut into your drywall to find the source of a leak. Use a utility knife to score a line about 10 inches (25 cm) 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 the 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. Advertisement

How do you identify the source of a leak in your house?

Expert Q&A

Search Add New Question
  • Question Is there a tool to detect water leaks? David Balkan 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 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 Yes No Not Helpful 22 Helpful 33
Ask a Question 200 characters left Include your email address to get a message when this question is answered. Submit Advertisement

Video

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 Helpful 0 Not Helpful 1
  • Once the leak is plugged, you should fix the peeling paint on the ceiling or wall. Thanks Helpful 5 Not Helpful 4
Submit a Tip All tip submissions are carefully reviewed before being published Name Please provide your name and last initial Submit Thanks for submitting a tip for review! Advertisement

You Might Also Like

Find a Water Leak UndergroundHow to Detect an Underground Water Leak Find a Roof LeakHow to Locate a Roof Leak Find a Water Leak in Your HouseHow toFind a Water Leak in Your House Detect a Water Leak Under ConcreteHow toDetect a Water Leak Under Concrete Dry Damp WallsHow toDry Damp Walls Fix a Leaking CeilingHow toFix a Leaking Ceiling Find a Leak in Your Swimming PoolHow toFind a Leak in Your Swimming Pool Test for MoldHow toTest for Mold Detect a Gas LeakHow to Determine if You Have a Gas Leak: Safety Tips & Signs Know if You Need a DehumidifierHow toKnow if You Need a Dehumidifier Find an Air Conditioning LeakHow toFind an Air Conditioning Leak Seal a Leaking RadiatorHow toSeal a Leaking Radiator Repair Peeling PaintHow toRepair Peeling Paint Troubleshoot Low Water PressureHow toTroubleshoot Low Water Pressure Advertisement

References

  1. https://www.youtube.com/watch?v=Gax-aAkmRGg
  2. https://www.mold-advisor.com/water-leak-in-wall.html
  3. https://extension.umn.edu/moisture-and-mold-indoors/dealing-and-preventing-mold-your-home
  4. https://www.health.ny.gov/publications/7287/
  5. https://www.washingtonpost.com/news/where-we-live/wp/2016/04/25/how-to-find-a-water-leak-in-your-home/
  6. https://www.mold-advisor.com/water-leak-in-wall.html
  7. https://www.bobvila.com/articles/how-to-find-a-water-leak/
  8. https://www.thestar.com/life/home-and-garden/how-to-find-the-source-of-your-leaks/article_565f2c7b-e4bf-577c-b445-36fcb60b5128.html
  9. https://www.thestar.com/life/home-and-garden/how-to-find-the-source-of-your-leaks/article_565f2c7b-e4bf-577c-b445-36fcb60b5128.html
More References (2)
  1. https://www.thestar.com/life/home-and-garden/how-to-find-the-source-of-your-leaks/article_565f2c7b-e4bf-577c-b445-36fcb60b5128.html
  2. https://www.washingtonpost.com/news/where-we-live/wp/2016/04/25/how-to-find-a-water-leak-in-your-home/

About This Article

David Balkan 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 490,073 times. 107 votes - 87% Co-authors: 13 Updated: July 9, 2025 Views: 490,073 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?YesNo

In other languages Portuguese Spanish German French Arabic Thai Indonesian Italian Japanese Vietnamese Dutch Hindi Russian Korean Turkish
  • Print
  • Send fan mail to authors
Thanks to all authors for creating a page that has been read 490,073 times.

Reader Success Stories

  • Sudhir H.

    Sudhir H.

    Sep 10, 2019

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

Did this article help you?

Yes No Advertisement Cookies make wikiHow better. By continuing to use our site, you agree to our cookie policy. David Balkan Co-authored by: David Balkan Professional Plumber Co-authors: 13 Updated: July 9, 2025 Views: 490,073 87% of readers found this article helpful. 107 votes - 87% Click a star to add your vote Sudhir H.

Sudhir H.

Sep 10, 2019

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

Quizzes & Games

Am I Being Gaslighted QuizAm I Being Gaslighted QuizTake QuizWhy Am I So Bloated QuizWhy Am I So Bloated QuizTake QuizHow Good Are My Survival Instincts QuizHow Good Are My Survival Instincts QuizTake QuizAre My Hormones Imbalanced QuizAre My Hormones Imbalanced QuizTake QuizDepression TestDepression TestTake QuizDo I Smell Bad QuizDo I Smell Bad QuizTake Quiz

You Might Also Like

Find a Water Leak UndergroundHow to Detect an Underground Water LeakFind a Roof LeakHow to Locate a Roof LeakFind a Water Leak in Your HouseHow toFind a Water Leak in Your HouseDetect a Water Leak Under ConcreteHow toDetect a Water Leak Under Concrete

Featured Articles

Remove Shorts from Search Results on YouTubeHow toRemove Shorts from Search Results on YouTubeWhat Are the Korean Animal Face Types? (And Which Type Do You Have?)What Are the Korean Animal Face Types? (And Which Type Do You Have?)Being the Little Spoon While Cuddling: Is It Better Than the Big Spoon?Being the Little Spoon While Cuddling: Is It Better Than the Big Spoon?115+ Funny “Get Well Soon” Messages to Make Someone Laugh115+ Funny “Get Well Soon” Messages to Make Someone Laugh110+ “Fun Facts” for Interviews, Introductions, & Icebreakers110+ “Fun Facts” for Interviews, Introductions, & IcebreakersHow Long Would You Survive In A Zombie Apocalypse?How Long Would You Survive In A Zombie Apocalypse?

Trending Articles

Which Fictional Character Would Crush On You?Which Fictional Character Would Crush On You?Who Is Secretly Crushing On Me Right Now QuizWho Is Secretly Crushing On Me Right Now QuizAttractiveness Score QuizAttractiveness Score QuizIs My Crush Pretending Not to Like Me QuizIs My Crush Pretending Not to Like Me QuizHypersexuality TestHypersexuality TestWhat Are the Gay Male Body Types (And Which Do You Have?)What Are the Gay Male Body Types (And Which Do You Have?)

Featured Articles

 Roast Someone in a Rap Battle (Plus the Best Bars of All Time)How to Roast Someone in a Rap Battle (Plus the Best Bars of All Time)What Turns a Girl On? 31 Things to Try on Your PartnerWhat Turns a Girl On? 31 Things to Try on Your PartnerLove AnalyzerLove AnalyzerSending Your Sweetie a Love Note? Here are 200+ Romantic IdeasSending Your Sweetie a Love Note? Here are 200+ Romantic IdeasExercise Your BrainHow toExercise Your BrainBe a Fun Person to Hang out WithHow toBe a Fun Person to Hang out With

Featured Articles

What Does Your Morning Routine Say About You?What Does Your Morning Routine Say About You?Develop Productive HabitsHow toDevelop Productive HabitsPractice Self CareHow toPractice Self CareWhat Song Matches Your Life Right Now?What Song Matches Your Life Right Now?Will 2026 Be Your Year? Reveal Your FutureWill 2026 Be Your Year? Reveal Your FutureUnderstanding the Most Attractive Face Shapes (& Determining Your Own)Understanding the Most Attractive Face Shapes (& Determining Your Own)

Watch Articles

Tie a Loop KnotHow toTie a Loop KnotMake Body OilHow toMake Body OilMake Almond MilkHow toMake Almond MilkWash White Clothes by HandHow toWash White Clothes by HandSkin a ChickenHow toSkin a ChickenClean Tile Floors with VinegarHow toClean Tile Floors with Vinegar

Trending Articles

What Are My Soulmate's Initials QuizWhat Are My Soulmate's Initials QuizChoose Your Own Adventure GameChoose Your Own Adventure GameYour Red Flag Based On Your Celeb CrushesYour Red Flag Based On Your Celeb Crushes151 of the Juiciest “Most Likely To” Questions to Ask151 of the Juiciest “Most Likely To” Questions to AskAm I Good at Flirting QuizAm I Good at Flirting QuizWhat Is Your Lip Type?What Is Your Lip Type?

Quizzes & Games

What Skin Type Do I Have QuizWhat Skin Type Do I Have QuizTake QuizWhat's Your Red Flag QuizWhat's Your Red Flag QuizTake QuizFinish the Phrase QuizFinish the Phrase QuizTake QuizCan You Pass Our Lie Detector Test?Can You Pass Our Lie Detector Test?Take QuizWhat Kind of Reality Check Do I Need QuizWhat Kind of Reality Check Do I Need QuizTake QuizAm I Smart QuizAm I Smart QuizTake Quiz wikiHow
  • Categories
  • Home and Garden
  • DIY
  • Plumbing
  • Water
wikiHow Newsletter You're all set! Helpful how-tos delivered toyour inbox every week! Sign me up! By signing up you are agreeing to receive emails according to our privacy policy.
  • Home
  • About wikiHow
  • Experts
  • Jobs
  • Contact Us
  • Site Map
  • Terms of Use
  • Privacy Policy
  • Do Not Sell or Share My Info
  • Not Selling Info
  • Contribute

Follow Us

×

Get all the best how-tos!

Sign up for wikiHow's weekly email newsletter

Subscribe You're all set! X --728

Tag » How To Find Where A Leak Is Coming From