Knowing leaky toilets and its waterproofing

Leaky toilets

No matter how we call our toilets, be it John, bathroom, restroom, place to poop or the throne, paying attention to its well being especially waterproofing leads to ours. Our homes in Singapore are mostly the apartment style of living. There are plenty of bathrooms and showers stacked on top of each other. Indeed, it goes without saying, waterproofing in toilets is required to comply with the Building and Construction Authority’s ( or BCA’s building standards. The last thing you need is a wet patch appearing and starting to leak in your shower room or living room or bedroom. Or your friendly Auntie living below coming to say hello with a vengeance.

Minor wear and tear contributors

Truth is waterproofing in bathrooms, and toilets suffer from wear and tear of many daily uses such as: 1. Waterproofing membrane deteriorating over time 2. External renovation your apartment 3. Minor seismic movements 4. Just living and using the toilet bowl, sinks and shower. 5. Pipes embedded in the concrete slab, walls and building structures

Commonly found joints and areas which may allow water to leak can be anywhere in the toilet or bathroom. I hope to provide options and an explanation of where such may occur.

Where can the leak start in your toilet?

I would prefer to review several common contributors to a leaky toilet. The leak doesn’t need a hole or crack visible to the naked eye. Knowing there is a problem with your toilet waterproofing comes from first noticing a wet patch or stalactites forming. The natural capillary effect of water movement that is due to water’s surface tension is often the culprit. (Check this out: Let us have a review of where the leak may start.

1. Piping – Polyvinyl Chloride Pipes (PVC), Copper, Polypropylene or similar (PPR), Stainless Steel These are common types of pipes used in homes in Singapore. I will discuss the various pros and cons of these types of pipes at another time. The variety of pipes themselves mostly do not deteriorate to the extent of leaking water. Sometimes, it is damage done to it (regardless of whether by accident or poor design), or the joints and connectors, that contribute to the leak. Connectors could crack or rust or the seal inside breakdown. In this aspect, there is a good reason why external piping is a good idea. Concealed piping is aesthetically pleasing, but if there is a leak, it can cause waterproofing issues for your toilet.

2. Wax ring at the base of the toilet bowl The often overlooked flush toilet is actually more complicated then one would think otherwise. It seems the today’s flush or squat toilet started from Thomas Crapper ( hence the term take a crap. Waterproofing is affected at the wax ring join between the sewage pipe and toilet flush. Ideally one should correctly use the flush toilet bowl. Not squatting or standing or rocking it.

3. Flushing tank has cracked There is also a chance that something has gone wrong with the water tank. It may have developed a fracture on the surface of the porcelain bowl, allowing water to leak. Depending on how bad is the crack, you shall have to consider replacing the tank.

4. Flapper problems The flapper is the seal between the flush tank and toilet bowl. Though not a moving component, the rubber (or cheaper plastic) seal may harden or become lost. Or if the tiny eyelet hole which holds the chain gets ripped off somehow, the flapper may start to drip water. Both will waste water but not affecting the toilet’s waterproofing.

5. Grouting leak at the joints or between floor tiles Grouting type used is a critical consideration leading towards water leakage affecting waterproofing in toilets. Tiny capillaries allow water to seep through slowly via reverse osmosis. Most of our tile flooring used in bathrooms have their surfaces glazed for waterproofing purposes. The problem here is the type of grouting will affect the durability of waterproofing in toilets or anywhere for that matter. There are basically two types of grouting used. Cementitious grouting and epoxy based grouting. Cemtitous grouting is cheaper and more commonly used unless the architect specifies otherwise. In the longer term, there is the issue of efflorescence (have a read of what is efflorescence in this link: and need to apply a sealer to the surface. Epoxy resin based grouting, however, do not. Cost indeed is higher associated with better workmanship when applying to tile.

6. Leaky bathtubs can be a real pain! Bathtubs are a joy to have, a paint to fix if it springs a leak. Common defects over time are either the faucet, joints somewhere, grouting or body, or the piping below the tub itself. As we use the bathtub, standing in it, going in and coming out, walking around it or just plain using it, wear may cause the alignment of the below tub piping to shift and leak. Water dripping over time will seep out from the side, below or anywhere gravity and capillary effect bring it. There is a tile access panel which can be removed, but no plumber will be happy to troubleshoot and hopefully locate the leak. Size of the joints and connectors vary from bathtub manufacturer to another. Over time, models and parts change. Worse is there is no manual for the plumber to work on. Meaning, how the original plumber fixed the piping is only known to that person. Leaky bathtubs may need a lot of elimination and experience especially if it is from the hidden parts.

If you’re looking for someone to fix your leaky toilet, contact Waterproofing Specialist Singapore

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