A Permanent Remedy For Toilet Tank Sweating
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Posted: Wednesday, December 24, 2008
by Joel Hendon
As I approached retirement, my wife and I looked for a home we could afford and that we would love to have and retire in. We found an old house, approximately 70 years old, which had been remodeled and refurbished, yet still needing some things done. It was in a quiet neighborhood and the street has very little traffic, in that it is only two blocks long. When we first looked at it, no one lived there and the owners were having repairs made. The full bath room had the entire floor torn out and they were replacing the joists underneath along with the flooring because it had rotted. We bought the house and when we moved into it, all looked well and good. It was in mid Autumn and we found no problems until cold weather set in.
I crawled underneath the house and could find no evidence of leaks or seepage there. But within the next several days, we found a wet spot now and then there underneath the tank. I began to feel the sides of the tank and found them beaded up with water droplets and the tank very cold to the touch. So it dawned on me that this was condensation dripping from the very cold tank in this room which was warm and humid, especially after our showers. There was no exhaust fan.
I knew that this dripping of moisture would again rot the new floor if something was not done very soon. Someone suggested that I buy a lining to go inside the tank which should stop the condensation. I found one and installed it inside the tank but I could see very little, if any, improvement. So we mopped the floor and wiped the moisture off the tank twice, or more each day. Then by chance, I found a valve in a Do It Best hardware store which boasted that it would stop toilet tank condensation. At first, I felt that this had to be a gimmick. But after looking at the valve and seeing the method and purpose of it, I understood that it would certainly work.
I bought one and hired a plumber to install it. In younger days, I would have installed it my self. The valve is not so ingenious, but a simple "Y" with one inlet having a screw-in valve shut off. It is also equipped with a backflow shutoff so when the valve is opened, it will not allow the cold water to flow into the hot water line. The side with the valve is to be connected to a hot water line and the open side connected to the original cold water line. You can shut the hot water side off during warm weather when it is not needed, then in winter you can open it enough to mix warm water going into the tank. This keeps the tank walls from becoming so icy cold and hence forms no condensation. The same valve has been installed now since1998 and I have had no more sweating of the tank.
These great little valves are available from most hardware stores, although many do not keep them in stock. Ace Hardware has one listed for $13.99. Lowes also carries one. The Do It Best Hardware stores carry a high quality one built by Mueller which sells online for $32.99. Mine is similar to the one carried by Ace Hardware. This is perhaps the best easy way to stop the tank from sweating. Another method which will usually do the job is to install a wall or ceiling exhaust fan. This will pull much of the humid air out of the room but may in some cases fail to stop the sweating completely. Also, if you don't have it already, they are costly to have installed.
To save one's floor from surely decaying is more than worth the cost and trouble of installing one of these valves.
This Article has been viewed 11,376 times. (Not updated in real-time.)Top-level comments on this article: (9 total)
I was advised to install an inexpensive styrofoam liner to stop sweating. Has worked since we built the house in 1982. Now the added feature is we contribute to reducing water consumption with the smaller capacity. -- Gerry McRae» left by Joel Hendon 4 years 150 days ago.
Hi Gerry, thanks for commenting. I can't recall what my liner was made from, but it didn't work. Our situation is somewhat unusual though. We have lived in other homes that did not sweat as this one did. I installed a new toilet a couple of years ago that is a water saver itself. And believe it or not, it still flushes better than the older one.
Great article! Well written and quite helpful for the future! Thanks again!Thank you Peter, for your encouragement. I really appreciate it.
hi joel,well, sounds like you found what you needed. i had a puddle of water next to the bottom of the toilet, and it did ruin the tile. i needed one of the above:)thanks for sharing,best regards,sueThanks Susan, when one has this problem and ignores it, it will rot the floors, flooring joists and even the sills if they are in contact with the moisture. Moist wood also attracts termites. So it is well worth it to get this done. Mine cost me less then $100. even with a plumber to install it. Of course, that was in 1998. Thanks for commenting
Thank you. My son's in-laws have this problem. Now I have something to tell them to do.Hi Beverly, thanks for commenting and I'm happy to hear that it may help someone out. I can't imagine why these valves are not advertised more. In fact, most stores don't even stock them, but can order one for you. Or you can order one yourself from HWI (DoIt Best Stores) online.
Hi Joel.I've heard about these valves. Luckily, we don't need them. We have the opposite problem. Our air is so dry that we sometimes run a humidifier. One of the benefits of living in the desert ... very, very little mold or mildew.Great article and good advice for those with the same problem.DianneThanks Dianne, and yes, you are fortunate not to be plagued with this excessive humidity. I just wrote an article the other day about the importance of the correct humidity level in you home. It is number swa413440 if you care to read it.I was stationed at Ft. Bliss, Texas for nearly a year during the Korean War and I assure you they don't need these valves out there. But they did need humidifiers. We use a humidifier regularly all winter, but then have excessive humidity in the summer.
» left by Martin from Millinocket, Me. 3 years 303 days ago.
I lined my tank. It did absolutely nothing. I was about to buy an insulated tank,when i heard of this valve. Installed one and, Walla- problem solved.Thanks for the article. Martin Jamieson ( )» left by Joel Hendon 3 years 303 days ago.
Thank you Martin for your comment. I'm glad to hear that you found out about the valve. It's well worth the installation.I've been told that an exhaust fan will serve the purpose of eliminating the high humidity in a bath room. But ours doesn't have one and would be an expensive chore to install one.Thanks again.
» left by Rozi from Northport, NY 2 years 336 days ago.
Yes, this article was extremely helpful. The best fix I found online.Thank you Rozi, for your comment and I hope you find that it remedies the problem. Shortly after we moved into this house some 18 years ago, we discovered the problem we had and we tried all kinds of things, put a lining in the tank, etc. but it kept sweating and even puddled on the floor. after a couple of winters it has ruined our floor and I ran into this valve for sale from HWI hardware. I knew the principle which was causing the tank to sweat so i new this made sense and tried it. We had to replace the floor (the sub-floor was not damaged) in the bath room and the valve did the job. Now some fifteen years later, the same valve is in place and we have had no more sweating.
» left by Anonymous 1 year 316 days ago.
Thank you for bringing this to my attention. I am off to Lowes right now to get this valve. The toilet has been sweating like crazy . I hope this works. I will check back and let you know.
RayThank you for reading my article and commenting Ray. My valve has been installed now for 13 years and I have had zero sweat problems since I installed it. Money well spent.
» left by Eric from Ohio 1 year 79 days ago.
I just decided to google said tank sweating problem,as both toilets in my home sweat profusely.....to home depot I go!....thank you for your thorough,helpful post.cheers!Thanks for reading and commenting, Eric. I'm sure you won't regret it. My original valve from 1998 is still doing the job. No sweat.