Hi – wondering if two different grout products are used when grouting walls vs floors. All ’tiles’ are slate from India – not my choice. In a small bathroom job, I’ve got:
-non-shower area: 12×12 floor tiles, with 4×4 wall tiles.
-shower stall: 2×2 floor tiles, with 12×12 wall tiles.
Would you use two different grout types for these applications? Which ones? Sanded grout for the floor, and non-sanded for the walls? The 4×4 wall tiles are tumbled slate.
Thanks.
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Replies
The grout type is based on the size of the joints that you are grouting.
1/8" or over sanded.
For smaller ones unsanded.
So Bill, other than the size of the joint, there is no difference with regard to whether one is grouting walls or floors?
No. Floor grout/wall grout is grout.Alternatives are epoxy-based, with spectralok being one of the more user friendly. Can sorta be good for a shower, but not neccessary for residential. And "user-friendly" means compared to standard epoxy grouts which can be a bear.Plus using epoxy over slate? Disaster waiting to happen. Gotta have skills to tackle epoxy. Even spectralok.A good modified sanded grout with mildewcide added would be just fine. For bath or non-bath, for showers or dry, for walls or floors.Since you're using a non-rectified tile, which indian slate most certainly is, your grout joints will be larger than 1/8th inch, thus the want for sanded grout.Mongo
Bill is correct, in addition when working with natural stone products, and slate most specifically, even in guaged slate, there is a good deal of variation in thickness. a wider grout joint is often used to allow floating of the grout to mask the lippage from one tile to another. Unless you have perfect tiles, or spend a lot of time setting them in plane, i'd go with a wide joint. Make sure you have sealed your slate before setting, and use a grout release before grouting. It will save you a lot of time. scrubing gout residue out of cracks just sucks.
Thank you all.<!----><!----><!---->
The grout mix is a polymer modified unsanded grout, by Flextile Inc. It is not an epoxy grout, so I should avoid a disaster. Obviously, I will need to get a sanded grout as well, as the 4x4 tumbled slate wall tiles (in non-shower area) are more than 1/8" apart.
I will seal (with SealerPro Stone Sealer) the slate faces before grouting, let the sealer cure, seal again, cure. Will keep sealer out of joints. Apply a grout release agent. Will look for an anti-mildew additive.
Then grout. Will have lots of grouting sponges & fresh water & patience. Damp sponge, not wet sponge.
Flextile says to let grout cure 21 days before applying a final silicone grout sealant. That seems like a long time and the shower will be in use. I guess the whole shower will need to be thoroughly cleaned before this final step...
Thanks for straightening me out on when to use sanded vs. non-sanded.
Edited 9/20/2006 12:05 am ET by Pierre1
note on cure times; it goes without saying follow the directions. most products i've worked with have a 7 day cure until you apply sealer. the idea is to allow the water in the grout to chemically bond with the other components of your grout (cement), after the initial 24 hrs of cure, the wetter the better, more moisture to cure with.
the real issue is to keep soap and hair products out of the grout. if you have to use the shower rinse it down throughly after using it until it gets sealed. a residue of soap or product might keep the sealer from penetrating the grout. good luck.
DIY'er here. Did a 6'x12' foyer in slate 12"x12" ... first timer. I was told that slate was hard to cut with a wet saw. Not true, it cut as easily as any tile. Laid the slate over 1/4" Hardibacker with thinset. I was told to seal the slate before laying it. I didn't. Used sanded grout in 3/8" space. Rather than using the "smear" technique to place grout, I used a grout bag and then worked the grout in with the float. Beautiful, and lots less mess and cleanup. Had no problem at all with cleaning the grout from unsealed slate. Here's a trick I learned for good grout shaping. As slate is uneven, when shaping, work from the low tile towards the higher one, leaving a "ramp" of grout between the irregularities rather than a proud sharp edge of the higher tile. Also, I like to take a grout saw and clean out all thinset from the grout space, vaccum, and then take a rag and water and clean any remaining thinset from the edges of the tile. Good luck!