Our tile guy said to not use anything but water to clean the tiled areas until the grout was sealed, because chemicals in various cleaners can permanently discolor the grout. Is there any truth to this? I'd swear I answered this, but I guess not! It sucks getting old! Your installer is right in that many CAN hurt the grout color. He's also right in that water should be all you NEED to clean it. But if you DO need something more than water, mix up some Oxyclean. It'll do just as good a job as chlorine bleach without hurting the grout the way bleach will. Does tumbled marble tile need to be sealed? We have tumbled marble 3x6 subways for a border and accent tiles in the master shower and tub deck, and 1x2 mesh on the shower floor. Our kitchen backsplash is also tumbled marble. If we should seal that, what is a good brand and what method is best to apply it? Although I don't believe in sealing grout, I DO believe in sealing stone. Two good recommendations would be Miracle 511 Impregnator, and Stone Tech Impregnator Pro. Both would be applied in the same manor-- take an old terrycloth towel, and rip it in half. Use one as the applicator, and the other, to wipe off the excess. Take the applicator, and wipe a liberal amount of sealer on, let it set for about 5 minutes or so, and then take the dry half and buff off the excess. Done. I just had my new bathroom tiled and my contractor (NYC area) did not recommend it. His bathroom and kitchen are not sealed. I think (but am not positive) that he also said that sealing was another way to make money and that once sealing is done it has to be done again in the future. With respect to sealing the grout, I agree with him 100%, including the part about it being a racket.

I saw the Q-seal last month. It does have a low sheen, but with the passing glance that I gave the booth it didn't look overly "filmy" or unnatural. But I didn't give it a real good look and the girl at the booth wasn't too technical, so I didn't dig or stick around too long. The basics that I recall: It it a lifetime seal, and the look you see is the look you'll end up with, since the product is already sealed. There's no chance of it changing color or shade or sheen as an unsealed stone might after it's been sealed on site. I asked if it was an epoxy or resin-based sealer, she didn't know. "It's baked in" is all she'd say. It has some sort of anti-microbial resistance. Not sure if that is a byproduct of the sealing process itself or if there is a secondary anti-microbial additive somewhere in the mix. Supposedly good for steam showers and wet areas. Regarding steam, I asked about vapor permeability of the sealer, she replied with a null and void expression. Tile edges are not factory sealed. So stains could enter through the grout and wick into the stone behind the sealer. That's why I asked about vapor permeability of the sealer. I was wondering if steam shower vapor could enter the stone through the grout and unsealed tile edges and become trapped in the stone body behind the sealer. Not a doom and gloom question but just one of curiosity. But I presume the sealed face is not vapor permeable based on some of the booth advertising text. Any on-site fabrication, bullnosing or edge profiling, those edges will have a different look and will have to be hand-sealed by the installer as the profiling will obviously remove the factory seal. Sanded grout scratching the sealer, she didn't know that one. I'm sure sanded could be used, the installed would just have to be careful like with a polished stone. It was more like a trade show drive-by than an in-depth investigation. But the mock-ups they had which were a couple of marbles, the stone looked good. The booth was busy and I got the person who was free, so don't let her lack of knowledge reflect poorly on the product. She just wasn't as technical as the others.

Mrs D-- I know I already answered you by email, but for the benefit of those searching the thread-- I'm not familiar with power grout. Not because it's not a good product (TEC has a terrific reputation), but because there are no distributors up here, unless you have a show room. That said, if your installer says he can do the installation without scratching the stone, I'd take him at his word. As for the sealer, personally, I'd prefer to seal it once-- when everything is done. Whichever way your installer wants to do it, I'd go with his recommendation. Some would rather seal twice, others all at one time.

The only things that need sealing are the slate, and if you wish, the grout. You don't need to worry about getting a little on the edges. It doesn't completely keep the grout from bonding. Not by a long shot. But at the same time, you don't want to douse the edges with sealer, either.