It's interesting to hear my customer's comments, concerns and reasons why grout needs to be sealed. As a tile contractor in California who has been in the tile industry since 1987, I have used several brands and types of sealers on several types of tile, stone, and grout.
The most common concern I have heard when discussing this issue is that the homeowner feels that sealing grout offers protection against water, especially with shower floors. I have heard them say that if they only sealed their grout, the shower wouldn't have leaked.
I can honestly say that there is no such thing ( to this date ) as sealer offering waterproofing, let alone water resistance to grout. Simply read the front/rear labels on grout sealers and you will see for yourself.
So why should you seal your grout? In my opinion, I feel that it is not necessary to, but if the customer feels more comfortable with it, then I will seal their grout with a very high quality sealer such as Aqua-Mix Sealers Choice.
I explain that I have sealed thousands of square feet of grout and have not seen any proven evidence that it is required.
I also discuss why I feel cleaning your grout with a high quality grout cleaner is really the key. You want a ph balanced product that is safe on grout. Heavy cleaners can destroy the cement content in the grout causing failure. I use a grout cleaner that has stayed cleaned for up to 6 months at the gym I go to. I was surprised to see the test area resist dirt for so long.
Long story short, if you really feel that it is necessary to seal grout, then use a high quality brand and expect to re-apply every 12 months. Don't expect sealed grout to perform better than non-sealed grout. I would imagine that if a company offered a sealer that was waterproof, they would push that feature and advertise it in a big way... I would even use it and promote it to my customers because it would HUGE.
If you are sick and tired of regular grout getting dirty quickly, cracking and absorbing water and drawing it under your shower floor causing mildew issues around the perimeter of your shower where it meets the walls, try using Epoxy Bond Grout. It is 99% waterproof, will not crack and never needs sealing. I use it several times each week for my customers.
jason
Q