Epoxy grouts are not water proof. That is a common misconception. They are nonabsorbent, and thus stain and water resistant, but they should not be sold as waterproof. I've seen quite a few contractors get in hot water by thinking they can waterproof a tile project with epoxy grout. 100% solids, old school epoxies, were a pro only proposition. They were way more than 10x the work of standard cementitious grouts, but the latest technology has made epoxy way more installer friendly.
Pulled trigger on porcelain tiles.
- Thread starter ct71rr
- Start date
PecosBill and gesoffen, I've been reading up and watching videos online about epoxt grout. I think I'm now sold on the idea of using it. My understanding is that you have to work in 50 sq.ft. sections. That is, dampen tiles with sponge, put the grout down, wipe off as much with the float as possible, let it stand for about a 1/2 hour, clean with scuff pad, wipe up with sponge, wait another hour and then clean with scuff pad and then sponge. I have about 1200 sq.ft of floor, so this will take some time. Will the grout set-up before I start the next section with fresh grout? About how long does it take to start to set up?
My suggestion is that you should not go more that 12" x 12" tile. If you have miss perfections in the floor, and laying it straight to the floor, you may have issues with aligning the tiles.
For the guy with the POR15 floor. If it was my floor, this is what I would do. Not sure if this would work in your situation though so keep that in mind. My floor was painted before, probably a long time ago, with some garage paint. Most of it was gone, but you could see spots where it was still present. Second, my floor was pitched in all the wrong directions. My car, was in the high spot in the garage. So all the water was going to my work bench area, and storage area. This pissed me off to no end.
So what I did, was a mud job on the entire floor. Basically ended going up 3.5" toward the back of the garage, and to nothing by the door. My pitch now flows the water to the center, and out to the garage door.
So, for the POR15 floor, I would grind it, if it was cheap, and not really worry about getting it all off. I've used it before, and it is hard stuff. Grinding it will most likely clog the **** out of the disks. The heat from grinding will break up the POR and most likely slow you down *********.
Thinset is expensive, but bonds well to a lot of things. So skim thinset over the POR15, lay down mesh, right away mortar, right away thinset on top of that, and lay the tile, no need to wait for the mortar to set. If you do 2" or so of mortar, you will be golden. If done like this, you can set the tile with a mallet, forcing pitch, and really setting your tile in stone.
I had crack in my floor too. What I did here is drill out/chisel out 1" - 4" holes. I did a lot of holes. Maybe every 4 - 6 inches, all on the loose piece. I have Hilti Jack Hammer, so I used that. I put 2' re-bar down each hole, and filled it with concrete, bonding it to the mud job that was coming over the top. Floor wiggled before when run over with a car. Nothing anymore. Solid.
You will not be able to set tile on a thick layer of thinset. Don't even bother. Mortar, and thinset above and below it. I learned this from an old Italian tile guy. All of his work was flawless. My cars, a nearly two ton Lexus GS430, RX350, and my friends Durango have been on my tile, jacked up for wheel and brake changes. Nothing happens to that tile. Nothing placed under the jack or anything.
For the guy with the POR15 floor. If it was my floor, this is what I would do. Not sure if this would work in your situation though so keep that in mind. My floor was painted before, probably a long time ago, with some garage paint. Most of it was gone, but you could see spots where it was still present. Second, my floor was pitched in all the wrong directions. My car, was in the high spot in the garage. So all the water was going to my work bench area, and storage area. This pissed me off to no end.
So what I did, was a mud job on the entire floor. Basically ended going up 3.5" toward the back of the garage, and to nothing by the door. My pitch now flows the water to the center, and out to the garage door.
So, for the POR15 floor, I would grind it, if it was cheap, and not really worry about getting it all off. I've used it before, and it is hard stuff. Grinding it will most likely clog the **** out of the disks. The heat from grinding will break up the POR and most likely slow you down *********.
Thinset is expensive, but bonds well to a lot of things. So skim thinset over the POR15, lay down mesh, right away mortar, right away thinset on top of that, and lay the tile, no need to wait for the mortar to set. If you do 2" or so of mortar, you will be golden. If done like this, you can set the tile with a mallet, forcing pitch, and really setting your tile in stone.
I had crack in my floor too. What I did here is drill out/chisel out 1" - 4" holes. I did a lot of holes. Maybe every 4 - 6 inches, all on the loose piece. I have Hilti Jack Hammer, so I used that. I put 2' re-bar down each hole, and filled it with concrete, bonding it to the mud job that was coming over the top. Floor wiggled before when run over with a car. Nothing anymore. Solid.
You will not be able to set tile on a thick layer of thinset. Don't even bother. Mortar, and thinset above and below it. I learned this from an old Italian tile guy. All of his work was flawless. My cars, a nearly two ton Lexus GS430, RX350, and my friends Durango have been on my tile, jacked up for wheel and brake changes. Nothing happens to that tile. Nothing placed under the jack or anything.
Like I said, Opticolor and SpectaLock have longer working times, and are much easier to work than a lot of the epoxy grouts out there.
Here is a link to the TDS: http://www.mapei.com/public/US/products/Opticolor_TDS_EA.pdf
I would not recommend a mud job to a non-professional. A true mud job takes skills that involve some training. Once you are in the 1.5-2" depths, unless you are really skilled, you would have to do it in lifts. Dry-packs involve a lot of compacting, and the thicker it gets, the harder to compact. Thinset is actually pretty inexpensive, even the two part system I mentioned in my earlier post, which is on the high side of thinset systems, is not a pocketbook buster. But I would never recommend the thinset embedded lathe method. It is too easy to end up with delamination problems. Thinset also does not bond to all things. Kerabond/Keralastic bonds to more than most, but you still need to remember than thinsets rely on a capillary bond, which means it needs some bite into concrete, or other substrate that it is being applied to. Concrete sealers are designed to seal the pores of concrete, thus inhibiting this capillary bond. http://www.mapei.com/public/US/products/Kerabondkeralastic_TDS_EA.pdf
As to setting in thick thinset, some think that is the way to set large format tile over a slightly imperfect substrate, but the correct material would actually be a medium bed setting mortar, such as: http://www.mapei.com/public/COM/products/UltraflexLFT_TDS_EA.pdf
You are probably right. I am not really sure how thinset would bond to POR15.
I also doubt it would delaminate, it's not like there is anything that will push up a layer of tile and cement. But like I said, I am not really sure about POR15 and how it would work under tile. My logic is that as long as the mud job has no voids or air pockets, the rest of the layers won't go anywhere when anything is over the tile. Not like the floor will slide out of the garage, or jump up. I do see problems if it was just tile over thinset over POR15 though.
And thinset is much more expensive than mortar, especially when you start using for more than just notch trowel thickness. I used over 100 bags of sand on my floor. Can't remember how many of cement. Can you imagine what that would cost in thinset?
And I used SpectraLock epoxy grout. I don't think I will use the regular grout ever again. At 1/8 joint, I was only able to cover 40 - 50sq ft per kit. Dry time was way over 6 hours. But I did all this in the winter, with garage hitting a high of 60F.
Thinset is not to be used beyond notch trowel thickness, that's why it's called "thinset". 
You are mostly correct, except for the delamination part. While tile and mortar are heavy, and floors are subject to compression, moisture can lift floors. Once that happens, microscopic movement can start breaking apart a mortar bed and bond lines. A floating floor system can work, but they are not designed to work with heavy loads.
Tile can make an extremely durable surface, when done correctly. It's usually best to at least check your planned installation system against acceptable TCA methods.
You are mostly correct, except for the delamination part. While tile and mortar are heavy, and floors are subject to compression, moisture can lift floors. Once that happens, microscopic movement can start breaking apart a mortar bed and bond lines. A floating floor system can work, but they are not designed to work with heavy loads.
Tile can make an extremely durable surface, when done correctly. It's usually best to at least check your planned installation system against acceptable TCA methods.
The only time you need to worry about freezing temperatures, is when moisture is an issue. The problem stems from water getting between the tile and the substrate, freezing, lifting the tile, and then breaking the bond. Once more, this is where Keralastic/Kerabond comes into play. It is resistant to saturation, and is also slightly flexible, so it withstands freeze/thaw cycles. Porcelain tiles are dense enough to withstand freeze/thaw themselves, as well. Here, in the PNW, where we endure freezing winters too, we still install porcelain tile in exterior situations, such as building siding, decks and patios, or walkways, and do not have problems, as long as they are installed correctly.
I too have installed tile on patios/decs, my own and family only. I am not sure if what I used is Kerabond, but I got the stuff from the tile store. Looks like milk, and kerabond rings a bell, so it might be what I used. But yea, NYC winters have not had an effect on any of the tiles thus far. 8 years for the oldest installation, and not one issue. And this is with snow, then melting snow, then ice sitting on them. Tiles are really durable, porcelain especially.
I honestly never though about doing my garage with it till Jack put me onto it on DIYForum. Now I can't see why anyone would do anything else, especially if the floor is in great condition. Seriously a floor jack, with a car on it, and nothing happens to the tile.
Epoxy get messed up all the time. Scuffs, tire marks, bubbles, installation is almost a coin toss if it will look good or not. Some of the horror stories make my eyes pop out.
Racedeck is nice, but you can't really clean it, and it also gets damage, plus it costs a **** ton. Never tried putting jack stands on it, but pretty sure it will make some permanent penetrations.
Had my floor been normal, and I didn't have to fix the pitch, I wouldn't have to pay someone to mix and lay mortar as I tiled. It would have been just thinset, kerabond, tile and grout. Well plus time.
You can see the progress with the mud job here.
http://www.garagejournal.com/forum/showthread.php?t=90047
I honestly never though about doing my garage with it till Jack put me onto it on DIYForum. Now I can't see why anyone would do anything else, especially if the floor is in great condition. Seriously a floor jack, with a car on it, and nothing happens to the tile.
Epoxy get messed up all the time. Scuffs, tire marks, bubbles, installation is almost a coin toss if it will look good or not. Some of the horror stories make my eyes pop out.
Racedeck is nice, but you can't really clean it, and it also gets damage, plus it costs a **** ton. Never tried putting jack stands on it, but pretty sure it will make some permanent penetrations.
Had my floor been normal, and I didn't have to fix the pitch, I wouldn't have to pay someone to mix and lay mortar as I tiled. It would have been just thinset, kerabond, tile and grout. Well plus time.
You can see the progress with the mud job here.
http://www.garagejournal.com/forum/showthread.php?t=90047
Would Kerabond be an alternative to Ditra? As I stated before, I'm going to be pouring the floor for the addition to the existing floor (which is 20+ years old). I'm worried about cracking along the seam between the floors. Plus, I'm not sure it there is a moisture barrier (plastic) under the existing floor. I haven't done the "plastic taped to the floor" test yet. Now I'm thinking I could probably get the entire floor repoured for alomost as much as I would have to pay for the Ditra ~ $1700.00. Then I would have a much better base to start with. 
Would Kerabond be an alternative to Ditra? As I stated before, I'm going to be pouring the floor for the addition to the existing floor (which is 20+ years old). I'm worried about cracking along the seam between the floors. Plus, I'm not sure it there is a moisture barrier (plastic) under the existing floor. I haven't done the "plastic taped to the floor" test yet. Now I'm thinking I could probably get the entire floor repoured for alomost as much as I would have to pay for the Ditra ~ $1700.00. Then I would have a much better base to start with.
I would never recommend Ditra in a garage. Ditra is a uncoupling membrane, and it does have it's uses, but it does have point load limitations. It can be used as a moisture inhibiting membrane, when installed with the correct accessories, but I see no reason why you would need that in a garage. If you are worried about waterproofing, for some reason, a better type product is a trowelable membrane. These range from latex to cementitious. These membranes also act as crack isolation membranes. Some fairly cheap insurance is Mapei Mapelastic HPG Membrane (I am starting to sound like a Mapei sales rep
). http://www.mapei.com/public/COM/products/MapelasticHPG_TDS_EA.pdf.pdfFor the cold joint situation, you must remember to honor all joints through your finish floor. Make sure that a joint in the tile lies over the cold joint, or cut a joint through the tile, and then fill with a flexible joint filler. Most grout manufacturers offer matching caulks to their grouts.
One thing to remember, if you use Ditra somewhere, you do not use a modified thinset. Because of the design, and the impermeable plastic construction, and the density of porcelain, there can be cure problems with modified thinsets. Schluter will not warranty a modified thinset over Ditra installation.
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les_garten
Banned
I had a problem with the last Caulk/Grout I used. It shrank and cracked like crazy. Any ideas on that? Also, if you spread that red membrane, I think it's red-guard or something, do you not use a modified over it?
I would only recommend Dirta over a wood sub floor. It is a decoupler. Meant to disconnect the wood floor from the tile above. Use it so that when the wood shrinks and expands, it won't pull the tile apart. Wood is a ***** that way.
Redguard is Custom Building Products version of Mapei's HPG. Yes, over either one of those, you would use mofified thinset.
The caulk shrinkage can be controlled by first putting in a backer-rod. The other way, which is a little more advanced, is to partially fill the joint with grout, and then bevel a V into it, to the bottom of the joint. You want to make sure that there is a clear path of caulk through the joint, in order to direct any movement through the caulk. You also need to remember that the caulk's job is to move, and at the extreme, tear or crack. Its job is to act as a sacrificial joint, that is easily patched when it cracks. Two side by side slabs will move independently, even if pinned or doweled. The idea is t make sure that movement does not cause cracking in the tile.
Still not the best solution in all situations. Backer-board, with a trowelable membrane, is usually a better solution. Many like Ditra because of it's quick application, but there are downsides to an uncoupling membrane, especially in high point-load situation. The best uses for uncouplers are where there is an extreme chance of substrate cracking or shrinkage, such as green concrete.
Would Kerabond be an alternative to Ditra? As I stated before, I'm going to be pouring the floor for the addition to the existing floor (which is 20+ years old). I'm worried about cracking along the seam between the floors. Plus, I'm not sure it there is a moisture barrier (plastic) under the existing floor. I haven't done the "plastic taped to the floor" test yet. Now I'm thinking I could probably get the entire floor repoured for alomost as much as I would have to pay for the Ditra ~ $1700.00. Then I would have a much better base to start with.
If the floor does not move, I would not worry too much. Don't use the Dirta in garage. That stuff will flex under a car, and crack everything above it. I would just tile over the cement. If the seam cracks, which I doubt it will, then you might have to replace that row to honor the seam below.
I say don't over-think it. Look at Jacks garage. He did it a while ago. Ceramic tile too. Everything holding up great. He had mis-perfections too. You are putting a really hard, durable tile on thinset, which will give you a hard level are for the tile. You would have problems if the slab moves, or you didn't use a trowel. Don't go crazy for this. Not rocket science. If a tile breaks, fixing it is really easy.
I've never used Dirta either. Just sayin.
The "seam" will crack. Two adjacent slabs move independently. There are multiple reasons for this, foremost, one will be a new slab, subject to more shrinkage than the existing slab, and second, two different slabs of differing size consist of differing quantities of mass. I have seen 1000sf slabs contract/grow 1/8" over a 40 degree temperature swing. Most people don't realize concrete moves, but it does. Throw in factors like heave, and you realize why every single tile or flooring expert tells you to honor all joints, whether cold, expansion, or control. It is more "rocket surgery" than people like to think.
les_garten
Banned
As the OP can see, Tiling can Lead to OCD and **** Retentiveness!
Some call this attention to detail.
Some call this attention to detail.
All great points, I never thought of the Ditra being crushed by the weight of my cars. Slick, I think I am at the point where I'm overthinking this. I think the route I will take is to put down a trowelable membrane, modified thinset, tile, epoxy grout. Thanks for all of the great advice everyone
As the OP can see, Tiling can Lead to OCD and **** Retentiveness!
Some call this attention to detail.
Keep in mind what PecosBill said about the two slabs. He does seem to know what he is talking about. I would still lay the tile over the seam, but have it in a way that the tiles meet there. So if you do see it splitting, you can address it right there.
I am not a pro at this. Just seen a lot of people lay tiles, and seen what worked. Got some practice while helping friends and family, all good.
It's the garage, don't go crazy. It will be better than what you currently have, you know what I mean.
I am not a pro at this. Just seen a lot of people lay tiles, and seen what worked. Got some practice while helping friends and family, all good.
It's the garage, don't go crazy. It will be better than what you currently have, you know what I mean.
horizontallyopposed
Well-known member
I just wanted to pass along my thanks to PecosBill who managed to answer many questions I had rolling around in my head.
For small cracks in a concrete slab and expansion cuts will a membrane suffice in those areas? I have stone and tile throughout my home. Concrete floor. The membrane plus thinset is all the tile guy used. On the lanai/patio he used the "red stuff." I have no problems with cracked tiles or travertine.
IN the garage I have a few hairline cracks and one big cut (on purpose) through the center of the slab. The garage was poured in a single setting and there is plastic underneath the slab. Once I sand/grind off the POR 15 will a membrane underlayment in those areas (small cracks, cut through the middle of the slab) combined with the higher end thinset mentioned in this thread be sufficient to lay 16" tile?
IN the garage I have a few hairline cracks and one big cut (on purpose) through the center of the slab. The garage was poured in a single setting and there is plastic underneath the slab. Once I sand/grind off the POR 15 will a membrane underlayment in those areas (small cracks, cut through the middle of the slab) combined with the higher end thinset mentioned in this thread be sufficient to lay 16" tile?
For existing small cracks, use a membrane like HPG or Redguard, and embed fiberglass reinforcing cloth into it, above the cracks. Cuts in concrete are Control Joints, which are designed to give when the slab is subject to movement. Expansion Joints are completely different, they are designed to move. The go completely through the slab, whereas Control Joints are only cut partially through it. To add to the confusion, there are Cold Joints where two slabs, usually placed at different times, meet. The one thing these all have in common is, you do not want to bridge any of these with tile. Now, to be honest, I have bridged Control Joints, but it is risky. If you are careful, and build a slipsheet from the Control Joint, to the nearest parallel tile joint, you might be able to get away with it, but that's on the advanced end of tile setting skills. Expansion and Cold Joints can't ever be bridged. The are always subject to movement, hence the name "Expansion". The joint in your garage is most likely a Control Joint, and not an Expansion Joint.
Like I said in an earlier post, your best bet is to layout your tile according to any Control Joints you are dealing with. Barring that, you can cut a joint through your tile, over the Control Joint, and then fill it with a flexible joint filler.
There is no problem with laying 16" tile, it will just be a lot easier to do if your slab is in plane. The larger the format of tile, the flater it needs to be.
For Expansion Joints, you can use the same method, but it is going to have to be maintained. A more durable system is an Expansion Joint Cover, but they are expensive, and stand out quite a bit.
Like I said in an earlier post, your best bet is to layout your tile according to any Control Joints you are dealing with. Barring that, you can cut a joint through your tile, over the Control Joint, and then fill it with a flexible joint filler.
There is no problem with laying 16" tile, it will just be a lot easier to do if your slab is in plane. The larger the format of tile, the flater it needs to be.
For Expansion Joints, you can use the same method, but it is going to have to be maintained. A more durable system is an Expansion Joint Cover, but they are expensive, and stand out quite a bit.