DRAINPRO Blog: Plumbing Basics

Common Causes of a Leaky Toilet and How to Choose the Right Toilet

Stop flushing your money down the toilet; replace or repair leaky toilets right away. The cost of leaky toilets usually goes beyond excessive water charges.Water damage and mold problems often multiply cash outflows if toilet leaks are not fixed immediately.

Common Causes for Under-the-Toilet Leaks

  • Older flanges break
  • Flange sits low in the floor
  • Over tightening ofthe flange nuts
  • Wax ring loses its seal when a rocking toilet sitting on an uneven surface has not been shimmed

Usual Reasons Tanks Leak

  • Worn tank washers, bolts or gasket
  • Gasket, pipe or bolt corrosion from water impurities, chemicals and/or age
  • Worn or loose feed line
  • Worn or loose fill valve gasket and/or washer

Other Common Toilet Leaks not Listed Above

  • Toilet leaks through cracked tank or bowl
  • Water overflows into the floor if overflow tub is obstructed
  • Tank overflows if float isn’t working properly
  • Tank water continuously leaks into the bowl if the flapper doesn’t seat properly due to grit buildup on the seal or flapper or if the chain is kinked

If you are sick of the ongoing repairs of an older toilet, perhaps installing a new toilet is the cure you need. Before plunging into a toilet purchase, avoid problems with a new unit by following our toilet shopping guide below.

  1. Measure the rough-in distance between the finished wall behind the existing toilet and the middle of the drain pipe so you will know the correct rough-in measurements before you begin shopping.
  2. Elongated toilet bowls are more comfortable but larger bathrooms better accommodate the typical 31” protrusion from the wall. Shorter elongated bowls are sometimes available, however. If not, round bowls are the best choice for smaller bathrooms since they measure 28” or less.
  3. Choose the most comfortable height. The standard toilet height is 14”; however, taller people, aging individuals and those suffering from immobility issues may benefit from a tall toilet.
  4. A wall mounted toilet system is attractive, but special installation and hardware is required to be sure the wall willsupport the toilet. Besides that, leaks may go undetected for an extended period of time since much of the action happens behind the wall, which will then create more problems. Often repairs on these units will require going into the wall as well. The standard tank and bowl system is easier to detect problems and to maintain should repairs be needed.
  5. Outstanding flushing performance is perhaps the most common feature sought in a toilet. Careful research and testing of showroom displays will help you choose the best toilet. For example, are you apt to easily clog a toilet? If so, you will need a toilet equipped with a large siphonic trapway outlet to allow more bulk material through and with larger flush valves to deliver water with more force and speed.


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