A question I was asked frequently in 2009 relates to sealers in tiled showers. So it came as no surprise that the first question I get in 2010 (this morning in fact) was: “What sealer should I use my shower?”

On average I get asked this question at least once a week, so it would seem that lots of people have got issues with staining in their showers. However, usually just a few seconds into the conversation and I realize that they are actually asking the wrong question.

The problem is that most of the people asking about sealers are really looking for last-minute water-proofers; something to make sure their newly installed shower does not leak. Typically, people will ask me something like this: “I have just had my shower tiled and now I want to put something on the grout to make it waterproof”.  At which point I have to explain that sadly, they have already missed that particular boat.

So just to clarify; the vast majority of sealers on the market are not intended to be water-proofers. They are instead stain resisters – think of them like filters or straining devices. Without doubt, most will indeed add some level of additional water resistance; water falling on a sealed grout joint will take longer to get through, will tend to bead on the surface and so the sealer will keep more of the water out for longer – but it is not 100% water proof – it is not intended to be. Indeed, if it is a good quality modern sealer, it should be designed to allow moisture vapour to be transmissible, if it can let water vapour out, then it can let some water in.

So my advice would be sure, go ahead and use a good grout sealer it will increase water resistance a little (or even quite a bit, depending on the sealer) and definitely add stain resistance, making ongoing cleaning easier. Just don’t rely on it to totally water-proof a leaky shower.

In my next post I will discuss ways in which to minimise the risk of water-related problems in showers. Notice though, that they are all part of the design and construction of the shower – water-proofing should be designed and then built-in to showers.

Copyright Ian Taylor and The Tile and Stone Blog.co.uk, 2013. See copyright notice above.