Reuben's Home Inspection Blog


Does the bath tub overflow leak? There's only one way to find out.

Many years ago, I learned about a bath tub leak that I never caught during my home inspection.  The seller didn't have any children and didn't take baths, so they never knew about the problem with the bath tub drain.  I did my standard inspection of the bath tub, which included filling the tub up with about four inches of water and then letting it drain.  I didn't find any leaks and never reported a problem.  

After the new owners moved in, the first time their children used the bath tub water began leaking through the kitchen ceiling.  

Why didn't I catch that leak?  

Bath tub overflowBecause I didn't test the overflow.  The first time the kids took a bath, they filled the water up as high as it would go.  When the water hit the overflow, it leaked right through the overflow in to the wall cavity because the overflow wasn't connected properly.  If the overflow drain at the bath tub isn't connected properly or has a worn out seal, it's going to leak, and sometimes profusely.

That was a real 'duh' moment for me.  I had never heard of other home inspectors testing the overflow, so I just assumed that doing this was beyond our standards of practice.  After hearing about the leak, I realized that this was something that I could have been testing all along, as long as I can view the bath tub drain via an access panel in the wall or floor.  I checked my Standards of Practice, and according to 6.1, A, 1, I'm supposed to inspect the plumbing fixtures.  What that means and how I do it is pretty much up to me.

From that point on, I started testing bath tub overflow drains, and I've since found dozens and dozens of bath tub drains that leak at the overflow.  I've also found that this test forces me to run a lot of water down the drains, and if the main building drain has a clog, there's a good chance that I'll find out about it after running all this water.

The video below shows the worst overflow leak I've ever found; this was at a house that was being 'flipped'.  Luckily it was an unfinished basement, so the leaking water didn't do any damage.


If you want to test your own bath tub overflow, it's very easy to do.  Just fill up your bath tub with water and watch the back side of the overflow when the water starts draining in to it.  If it's not working right, you'll know.

Reuben Saltzman, Structure Tech Home Inspections


Comment balloon 44 commentsReuben Saltzman • June 28 2011 06:02AM


Reuben, My in-laws had a problem with this, same situation essentially, their grandkid was playing in the tub and splashing water everywhere.  The overflow leaked, water went in the wall and then down to the main floor ceiling in the kitchen.  Drywall needed repaired in addition to the plumbing fix needed.  Fortunately they did have the access panel to get to the piping.

Posted by Liz and Bill Spear, RE/MAX Elite Warren County OH (Cincinnati/Dayton) (RE/MAX Elite 513.520.5305 about 7 years ago

Very useful post, I can see how this can be easily missed. . thank you for posting it! 

Posted by Fernando Herboso - Broker for Maxus Realty Group, 301-246-0001 Serving Maryland, DC and Northern VA (Maxus Realty Group - Broker 301-246-0001) about 7 years ago

Hello Rueben,

Is this why they invented "showers" LOL

I do the same inspection procedures. Some don't like it. They say I'm wasting water.

Clint McKie

Posted by Clint Mckie, Desert Sun Home, Comm. Inspection 1-575-706-5586 (Desert Sun Home, commercial Inspections) about 7 years ago

Great information, and thanks for sharing the video!

Posted by Tamara Inzunza, Close-In Alexandria and Arlington Living (RE/MAX Executives) about 7 years ago

Liz & Bill - kids are usually the culprit for this one :)

Fernando - I hate to think about how many I may have missed in the past.

Clint - wasting water?  Cry me a river!  That's a new one for me.

Tamara - thanks.

Posted by Reuben Saltzman, Delivering the Unbiased Truth. (Structure Tech Home Inspections) about 7 years ago

Reuben, great blog on an issue that rarely comes up.  Nicely done. 

Posted by Don Barrett (Integrity Real Estate Services) about 7 years ago

This is great!  I've never had an inspector check this before and will make sure to ask from now on. Re-blogging as well.

Posted by Coral Gundlach, Real Lives. Not Just Real Estate. (Compass) about 7 years ago

A easy to miss detail. Something i doubt many people check....

Posted by Scott Fogleman, New Home Team (New Home Team 804-573-9592) about 7 years ago

I have been through many inspections and you are right they do not test the over flow.


Great post

Posted by Keith Lawrence, ABR, CDPE, SFR, 203K Specialist (RE/MAX Properties) about 7 years ago

My favorite inspector does check this, I'm so proud of him.  Although, the way kids take baths, I'm not sure how you could tell what leaked and what was splashed.

Posted by Tracie Cope, ReMax 360 - (Granville, Newark, Heath, Buckeye Lake & all of Central Ohio) about 7 years ago

Reuben, I have worked with perhaps ten different home inspectors in my time, and I have never seen one check the bathtub overflow... yet I can see how testing it has value...

Posted by Chris Smith, South Simcoe, Caledon, King, Orangeville Real Esta (Re/Max Chay Realty Inc., Brokerage) about 7 years ago

Hey Reubs!  On new construction I pop the overflow caps off and look inside for purple primer and to see if the drain pieces are glued. Then I test the tub.  It is amazing how often the overflow drain is not connected!

Just yesterday (new construction) I had one that the plastic cover had not been removed from the drain cap, meaning the drain pieces probably had never been connected, and another that had no purple primer and I could not see glue, and it leaked! I found the same on a flip not long ago as well.  Flips aren't too surprising though.

On older construction, if there has never been a repair under the tub it has probably never leaked!

Posted by Jay Markanich, Home Inspector - servicing all Northern Virginia (Jay Markanich Real Estate Inspections, LLC) about 7 years ago

Good post Reuben.  I've never seen an inspector check the tub  overflow, but will suggest it in the future. 

Posted by Howard and Susan Meyers (The Hudson Company Winnetka and North Shore) about 7 years ago

Reuben, I can see where this would be an easy one to miss. Thanks for the info.

Posted by Michael Setunsky, Your Commercial Real Estate Link to Northern VA about 7 years ago

That's a new one for me too Reuben and it is no something I test for. You'd have to fill to the overflow and have access to the wall cavity at the head of the tub. This is commonly not accessible. Plus letting that much water spill may cause a liability issue for you.

Posted by Robert Butler, Montreal Home Inspector | Aspect Inspection (Aspect Inspection) about 7 years ago

and don't the sellers LOVE when you find a leak like that.  Not just because you've found a leak, but also because you now have huge water damage in the center of the family room ceiling.

Posted by Alan May, Helping you find your way home. (Coldwell Banker Residential) about 7 years ago

Reuben - Who knew? I've not had anyone have a problem with this. I think we just expect it to work properly. I'm sure your clients felt you were worth your weight in gold!

Posted by Carla Freund, Raleigh - Cary Triangle Real Estate 919-602-8489 (Keller Williams Preferred Realty) about 7 years ago

I have never seen an inspector fill the tub to check that, which would be so important on thesecond floor of a home. There's an invention waiting to be made. A suction adapter that allows a quart or 2 at the overflow to test.

Posted by Ed Silva, Central CT Real Estate Broker Serving all equally (RE/MAX Professionals, CT 203-206-0754 ) about 7 years ago

Hi Reuben: I do not believe that I've seen an inspector fill the tub and I honestly hadn't given it much thought myself.

Question: when you're doing the test, how do you prevent the leaking water from doing damage? Is it possible to catch it all with towels?
Thanks for sharint it!


Posted by Bruce Kunz, REALTOR®, Brick & Howell NJ Homes for Sale (C21 Solid Gold Realty, Brick, NJ, 732-920-2100) about 7 years ago

I learned this too the hard way one day on a rental that had repairs...Had to have the plumber return 1 week later and correct...Good to know and share  post....thank you Reuben....

Posted by Richie Alan Naggar, agent & author (people first...then business Ran Right Realty ) about 7 years ago

Don & Judi - I'm glad this rarely comes up.  Makes me feel better about all the ones I never checked.
Coral - I've never seen anyone else do this either.

Scott - yeah, very easy to miss.

Keith - maybe this post will inspire some inspectors :)

Tracie - oh man, don't I know how those kids make a mess.  I have a 3 1/2 year old son who can turn our bathroom in to a complete disaster during bath time.

Posted by Reuben Saltzman, Delivering the Unbiased Truth. (Structure Tech Home Inspections) about 7 years ago

That's called genetics Reubs.  Probably paternal.

Posted by Jay Markanich, Home Inspector - servicing all Northern Virginia (Jay Markanich Real Estate Inspections, LLC) about 7 years ago

Chris - yeah, I'd definitely not a 'standard' test.

Jay - you're the man!  I never pop the caps off.  I might have to start now though...

The one thing I find on older houses is that sometimes there will be a bathroom with a tub that hasn't been used for 20 years.  Those leaks are always a surprise for the owners, I'm sure.

Howard and Susan - as long as the ceiling doesn't get damaged, it doesn't hurt to check.

Michael - definitely.

Robert - whenever I don't have an access panel to check the overflow, I smile inside just a little, as it makes my job that much easier.  One more thing I don't have to check!  You're right, doing this type of test will increase our liability, but will also decrease the number of problems that the new homeowner might encounter later on. 

Doesn't every plumbing test we do increase our liability?  I mean, hey, if you test a bath tub and the drain isn't connected, water is going to dump all over the ceiling.  I guess that risk is just a part of our job.  By the way, that video was an anomoly - I've never had that much water spill before or after.

For the video, I was inspecting a flipped house with a client that I've known since I was about five.  I asked him to watch the bath tub overflow while I inspected the attic, and to shut the water off at the bath tub if the overflow leaked.  When I got done inspecting the attic, my client was texting on his mobile phone, and had completely forgotten about the bath tub!  Luckily there was no damage done.

My standard approach to testing the overflow is to fill the bath tub with cold water, and check on the bath tub every couple minutes.  Once the water level starts getting close to the overflow, I just stop what I'm doing and hang out behind the tub for a minute or two, waiting for the water to start draining in to the overflow.  If it starts leaking out, I immediately shut the water off at the tub and pull the drain.  I also bring a towel to every inspection so I can clean up any little spills.

I haven't yet had a single problem doing this test, and I've done this hundreds of times.

Posted by Reuben Saltzman, Delivering the Unbiased Truth. (Structure Tech Home Inspections) about 7 years ago

Alan - Thankfully, I've never had a problem doing this test.  I chalk it up to a little bit of luck and a lot of attentiveness.  See my comment above to Robert. 

Carla - and really, how many people even take baths?

Ed - that's a great idea!  That would save me so much time!

Bruce - see my comment above to Robert (#23).

Richie - it seems like you've learned most things the hard way, through your rental properties ;)

Posted by Reuben Saltzman, Delivering the Unbiased Truth. (Structure Tech Home Inspections) about 7 years ago

Jay - absolutely!

Posted by Reuben Saltzman, Delivering the Unbiased Truth. (Structure Tech Home Inspections) about 7 years ago

You'll LOVE this story.  And Robert!

With new construction (or flips) nothing has really been tested with time. The home inspection is the first test!

Once when I checked to see if the plumbing had been glued, and thought it had not, I tested it and the overflow valve leaked.  So my client didn't trust anything.

He asked me to test the drain hole under the drip pan where the washing machine would go. I had certainly NEVER done that! So I did, and guess what!?  Yepper!!

And, AND, the builder was mad at me for causing damage to the drywall ceiling and floor underneath!!

This was many years ago.  I remember it because the client was Asian.  The house was FULL of family!  And the drip pan leaked through a light fixture onto hardwood floors.  The whole crew saw it and let out a long, "Ohhhh!"  Their Asian Oh does not sound like our English Oh, you should know.

Did I have liability?  Of course not!  But the builder was mad at ME, of course!  It was my fault.

I went straight to my corner beside the piano...

Posted by Jay Markanich, Home Inspector - servicing all Northern Virginia (Jay Markanich Real Estate Inspections, LLC) about 7 years ago

Reuben, I pretty much assume they are going to leak and inform my buyer/client accordingly.  I would say that around here only about 10 percent of tubs have any view of the connection.

Posted by Charles Buell, Seattle Home Inspector (Charles Buell Inspections Inc.) about 7 years ago

Great tip. Most of the time buyers do not test this type of leak, and I guess if they don't bath or overflow the bathtub, they will not find out about it.

Posted by Eileen Hsu, LICENSED REAL ESTATE SALESPERSON (Douglas Elliman Real Estate) about 7 years ago

Jay - I DO love that story!  I can picture the entire thing playing out.  Testing the washing machine drip pan is one that I haven't tested yet.  How did you do it?  Pour a bucket of water down?

Charles - no view of the connection? So what happens when the wedding ring goes down the bath tub drain?  ;)

Eileen - exactly.   It's not a problem that most owners will ever experience.

Posted by Reuben Saltzman, Delivering the Unbiased Truth. (Structure Tech Home Inspections) about 7 years ago

Reuben, you'd think when they built the house they would have connected the overflow properly! I have seen inspectors fill the tub to check overflow. It seems like a waste of water, but better to know than have it ruin drywall after move-in.

Posted by Pamela Seley, Residential Real Estate Agent serving SW RivCo CA (West Coast Realty Division) about 7 years ago

I had an old claw foot like that and the overflow just spilled out on the floor. So does this mean it should have been hooked up to something???This was in a rental property....but I am sure that is not surprise to you.

Posted by Rosalie Evans, The Evans Group, Sioux Falls, SD Homes For Sale (Meritus Group Real Estate) about 7 years ago

Sí, Señor, un galón, más o menos.


Posted by Jay Markanich, Home Inspector - servicing all Northern Virginia (Jay Markanich Real Estate Inspections, LLC) about 7 years ago

Glad to see that you do this! We do too.

Posted by Atlanta's Home Inspector, David Lelak IHI Home Inspections, Experience the IHI Difference (IHI Home Inspections 404-788-2581) about 7 years ago

Reuben, I've never, ever seen an inspector check the overflow. In fact, I seem to remember on some occassions they don't even check stall showers if they're over a finished space. Seems odd to me now.

Posted by John M. Scott, Broker / Owner San Francisco Bay Area (BRE # 01442690, Scott Keys Properties) about 7 years ago

I've seen the overflow checked but not at every inspection. I will have to remember this at the next one.

Posted by Christine Smith, Exclusive Buyer Agent & Attorney, Canton, MA (Buyers Brokers Only LLC - about 7 years ago

Thanks for the info.  This reminds me of one of the investment homes I came across, the fourplexes in a subdivision all have the same problem.  Several of the units have water damages in the ceiling of the first floor area, right below the bathtub on the second floor.  This is a good work item to add to the to-do list for home inspectors.

Posted by Irene Lai-Chan, M.S., REALTOR (Rando Real Estate) about 7 years ago

Well thanks for answering guys. You are right about the liability of course. I'd want to find a way to check the overflow without filling the tub. There has to be a practical way to do that. You still need and access panel behind to get into the wall cavity. Many of the homes here don't have them.

Posted by Robert Butler, Montreal Home Inspector | Aspect Inspection (Aspect Inspection) about 7 years ago

Hi Reuben, Most of our tubs don't has an access panel. I do fill the tub with water. I had one inspection where I had tested the tub, then went into an adjoining bedroom closet (because that's where the attic access was) and the carpet looked odd. So, I touched it... felt fine, then I put my moisture meter on was wet, huh,... I pulled the carpet back a little and the floor was soaking wet! Evidently in this complex, the builder didn't seal the drain and this happened in a lot of the units. I only caught it because of the attic access. We can never catch everything in an inspection, and this was a new one on me. enjoy the 4th! jay

Posted by Jay Lloyd, Allpro Home Inspection (Cape Coral Florida) about 7 years ago

Pamela - that's exactly it.

Rosalie- I'm really not sure.  Maybe it wasn't a bath tub at all... maybe it was a convenient way of pouring water on to the floor so you could mop it ;)

Jay - If I ever test one of those, I'll think of you.

David & Bonnie - good stuff!

John - no checking shower stalls if they're over a finished space?  WHAT?  How would the buyer know if it leaked?  Would they need to call a thorough home inspector?

Christine - I guess it's a matter of personal preference of the inspector.  I don't like apologizing for stuff... as in "sorry I didn't catch that, but that's not part of my service..."

Irene - I see a lot of ceiling stains below bath tubs in condo units, that's for sure.

Robert - If you come up with a way to test the overflow without actually filling the tub, please be sure to let me know about it.

Jay - good story :)  I always tell my clients that it's better if I find out about the problems during the inspection, not them while they're living there.

Posted by Reuben Saltzman, Delivering the Unbiased Truth. (Structure Tech Home Inspections) about 7 years ago

You write some extremely interesting blog posts that answer many questions! Glad I found you.

Posted by Barbara-Jo Roberts Berberi, MA, PSA, TRC - Greater Clearwater Florida Residential Real Estate Professional, Palm Harbor, Dunedin, Clearwater, Safety Harbor (Charles Rutenberg Realty) about 7 years ago

Barbara-Jo - thanks, me too :)

Posted by Reuben Saltzman, Delivering the Unbiased Truth. (Structure Tech Home Inspections) about 7 years ago

I just wanted to thank you for this page and video. The bathroom shower in the apartment above me has been leaking into my apartment for over a week and the plumber has been at his wits end trying to figure out what's leaking. It never leaks when he's here, no matter what he tries, and he's replaced so much already in the hopes that the problem will be resolved. Using a flashlight, I've watched and witnessed exactly what is happening in your video. Now I can communicate what is happening to the plumber. Thanks for giving me the means to do that. :)

*crosses fingers*  Let's hope it will stop raining in my apartment once he's done.

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That's why it is so important to hire a trusted experienced inspector who will check everything properly during home inspection. 

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