Slate flooring - PeachParts Mercedes-Benz Forum

cmac2012 · #1 12-20-2009, 12:43 PM

I have a client who wants to put slate flooring (or maybe some other tile but slate is his preference) in his 260 sq. ft. living room in a condo he's invested in. I've not installed slate but have done other sorts of tile and from my web research, it's not that much different.

This will be on a concrete slab, I'm wondering if I should put down a Schluter-KERDI sort of product to minimize the risk of cracking. The thing is about 30 to 40 years old - I imagine the concrete will be pretty well stabilized by now. I haven't seen it yet - we've just left the old carpet on it for use as a giant work blanket. I imagine that if it shows cracks when I finally see it, that would be all the more reason to install the KERDI.

Every site I've perused says to seal it before grouting, else the grout color invade the pores and rough texture of the slate.

t walgamuth · #2 12-20-2009, 04:03 PM

I didn't read the whole blurb but it looked to me like that is for keeping moisture from going throught the porous tile and damaging the sub strate as in a tile over wood framing. It does not sound like it applies in your case.

cmac2012 · #3 12-20-2009, 05:07 PM

Quote:

Originally Posted by t walgamuth

I didn't read the whole blurb but it looked to me like that is for keeping moisture from going throught the porous tile and damaging the sub strate as in a tile over wood framing. It does not sound like it applies in your case.

That is its primary function but it also serves as a shock absorber for small cracks, preventing them from migrating through the tile. It's an extra step - you have to put down a thin coat of thinset, then the s-Kerdi, and then the tile.

t walgamuth · #4 12-20-2009, 10:08 PM

I don't suppose it can hurt, but it looks to me more for a wooden floor system which will move around with the seasons.

davidmash · #5 12-21-2009, 12:11 AM

I put something else down when I did my floor. I had some hair line cracks in the slab and I went to a tile only specialty place. They sold me a 'rubber' type thing that had a thin layer of fabric on the back. I rolled out some special contact cement (clear like water) that reacted with the rubber and laid it out n the crack. I was told it would allow a little movement (settling) and not crack the tile. So far the tile has been down almost 6 years and no cracks. I did lay slate by the way and they are 16x16.

The membrane was quite thin as I recall, maybe the thickness of a credit card or a credit card and a half. It's the red stuff on the bottom of the first picture.

cmac2012 · #6 12-21-2009, 12:52 AM

Now that's some good feedback. I see you only put it over the crack which would cut down on labor. This floor has been around long enough that wherever it doesn't have any cracks, I'm willing to call it good. I mean it might not have any at all but I'd be real surprised.

I'd like to go 16 x 16. I want to get in and out of this job and those would move it along.

davidmash · #7 12-21-2009, 10:33 AM

I do not remember the name (if you need it, the place is down the street from me and I can go ask) only came in the strips you see in the picture. The house was not as old as the one you are working on (15 years old) but the assumption was that it was not going to do anything more. I think we may have been wrong as next door just put in foundation supports/jacking because it settled. Anyway. So far no issues and the floor has been down about 6 years now.

cmac2012 · #8 12-21-2009, 03:06 PM

Thanks but I can probably find it. The Sch-KERDI comes in 48" wide rolls, it has a sort of fiberglass spun fabric on both sides, and the recommendation is to put it down with thin-set on both sides, well, the second coat for placing the tile. I like the sound of your product better.

We used the KERDI on one of those bathrooms with no screen for the shower, just one big sloped floor. Sort of a trendy thing - not sure how much it will catch on. No leaks so far. Another guy put the KERDI down and I had some small problems in the corners where he had more thin-set build up under it. The tiles were sorta thick so I just ground down the corners on the underside so I wouldn't have to have a thicker thin-set base in the whole room. I figure no one steps right in the corner so any extra weakness wouldn't be a problem.

Skid Row Joe · #9 12-21-2009, 03:30 PM

Quote:

Originally Posted by cmac2012

I have a client who wants to put slate flooring (or maybe some other tile but slate is his preference) in his 260 sq. ft. living room in a condo he's invested in. I've not installed slate but have done other sorts of tile and from my web research, it's not that much different.

This will be on a concrete slab, I'm wondering if I should put down a Schluter-KERDI sort of product to minimize the risk of cracking. The thing is about 30 to 40 years old - I imagine the concrete will be pretty well stabilized by now. I haven't seen it yet - we've just left the old carpet on it for use as a giant work blanket. I imagine that if it shows cracks when I finally see it, that would be all the more reason to install the KERDI.

Every site I've perused says to seal it before grouting, else the grout color invade the pores and rough texture of the slate.

I would use Compotite Gold anti-fracture, roll-out membrane. Price is less than all the rest, and it's the most tested anti-fracture membrane in the history of the Ceramic Tile Institute - Los Angeles, CA. Google Compotite for a dealer near you.

As far as 'sealing before grouting?' Sure - use which ever sealer you are going to eventually seal the slate and grout joints with. Aqua Mix would be a good choice - you'll just have to determine which one to use - they have several.

Both product lines are highly available in CA. - since they are California-based companies.

davidmash · #10 12-21-2009, 11:35 PM

I laid over 800 sq. We did not seal it before grouting. I used a med gray grout but i had no issues even with the oranges and reds in the tile. Cleaned up quite easy except for the nooks and crannies of the slate but that has nothing to do with not sealing it as far as I can tell. Still have not sealed it 5 years later. Cleans up great with some 409 or Clorox cleaner. Even the kitchen is fine.

cmac2012 · #11 12-22-2009, 02:40 AM

Quote:

Originally Posted by Skid Row Joe

I would use Compotite Gold anti-fracture, roll-out membrane. Price is less than all the rest, and it's the most tested anti-fracture membrane in the history of the Ceramic Tile Institute - Los Angeles, CA. Google Compotite for a dealer near you.

As far as 'sealing before grouting?' Sure - use which ever sealer you are going to eventually seal the slate and grout joints with. Aqua Mix would be a good choice - you'll just have to determine which one to use - they have several.

Both product lines are highly available in CA. - since they are California-based companies.

Haven't heard of that one. Sounds promising. I went to their web site and filled out the small form to request distributor info.

t walgamuth · #12 12-22-2009, 06:08 AM

The slate is pourous and will absorb bright colors like wine if not sealed. Just adds to the patena, actually.

CSchmidt · #13 12-22-2009, 08:25 AM

Davidmash,

Beautiful floor... very nice work.

Chuck

Skid Row Joe · #14 12-22-2009, 02:44 PM

Quote:

Originally Posted by davidmash

I laid over 800 sq. We did not seal it before grouting. I used a med gray grout but i had no issues even with the oranges and reds in the tile. Cleaned up quite easy except for the nooks and crannies of the slate but that has nothing to do with not sealing it as far as I can tell. Still have not sealed it 5 years later. Cleans up great with some 409 or Clorox cleaner. Even the kitchen is fine.

Do you need a 'sealer?' No, however - your floor could benefit from a sealer that enhances (darkens-richens the appearance) of the stone. I've used Aqua Mix's 'Stone Enhancer' on the slate on my Texas home's patio - exposed to the weather/direct sunlight - for almost 10 years now - with no change to it's appearance. Slate is similar to granite - in that it is somewhat indestructible, i.e. extremely non-porous - unlike marble, limestone/travertine.

davidmash · #15 12-23-2009, 12:15 AM

I sealed the back patio. I had some slate left over so I used it out back. They do have different kinds of seal as far as the look is concerned. There is a wet look sealer that gives it a bit of a sheen and makes it look darker. I used a neutral seal. I dries with out affecting the appearance of the stone. I personally like that look better.

I have 6 cats and all manner of stuff has been on the floor. Wine, juice, food, poo, vomit... you name it. So far no stains. I probably should seal the stone (at least in the kitchen) but I just have never had the motivation.

Quote:

Originally Posted by CSchmidt

Davidmash,

Beautiful floor... very nice work.

Chuck

Thanks. When we started to lay it (first pic) I got really scared. It looked very dark and I was not sure how it would turn out. Once the grout went in I knew I made the right choice. Now 6 years later, clean up is a breeze and we love it. It has taken on a nice patina and we are very happy. Who ever buys the house will have to love tile floor because it is not coming up. That much I promise.