Replies

1. 
   davidmeiland | Apr 24, 2011 11:11am | #1

   The sealer (or lack thereof) really makes no difference, as far as the waterproofing of the shower floor and walls is concerned. It probably doesn't make any difference to the tile either--it's not going to prevent water from getting into the grout or the tile itself, over the long term. In my opinion your builder would have been better off to advise you against using a porous stone in a shower in the first place (porcelain tile is a better choice), and hopefully he installed a first-class surface-applied waterproofing system directly under the stone, rather than a typical mortar bed with waterproofing behind it.

2. 
   user-270695 | Apr 24, 2011 01:43pm | #2

   Porous stone is used all the time in showers and I agree that a waterproof substrate is key in any install. Sealer helps to keep the grout and stone clean. Is is recommended by all pro's and industry "best practice." It should be re-applied per the manufacturers instructions, usually every 2-4 years. It is a little concerning that your ?installer? doesn't know this.

   From the NTCA website:
   http://www.tile-assn.com/Common/AskTheExperts.aspx?mid=40#5

   "Will sealing make my tiles or stone maintenance free ?
   Nothing is maintenance free! Sealing makes your surface easier to clean. contanminants can sit on the surface longer, so you have more time to clean up before any staining occurs. On some unsealed tiles and stone, staining can start immediately. Think of your stone sealing product as a bottle of time. No stone sealing product will make a porous surface stain-proof, but will make it highly stain resistant. Using the correct stone cleaning products also makes a difference."

3. 
   Natur Haus | Apr 24, 2011 04:39pm | #3

   Definitely seal it. Sealer is not waterproof but more of a deflective moisture protection measure. Sealing the grout is even more important in my mind, especially if it is sanded grout.