SpectraLOCK logo

If you have read anything on either of my websites you should know that I tell everyone on the face of the planet who will listen (all three of them) that Laticrete’s SpectraLOCK is the only epoxy grout I will use – period. So rather than just talk smack I’m gonna show you why.

You see the bottom of that logo up there? The part that says ‘Grout that Locks in Color and Blocks Out Stains’? I’m going to put that to the test. And being the kind of warped individual I am – I’m gonna do it in the most ridiculous, convincing way I know how.

Since I have kids I happen to know what the most vile, dangerous, and toxic staining substance on the face of the planet actually is. It is not red wine, a sharpie, or grape juice. Not even close.

It’s cherry kool-aid.

If you have kids you know exactly what I’m talking typing about. If I even set my beer Pepsi near a cup of cherry kool-aid it turns pink through either osmosis or sheer fright, I’m not sure which. This stuff is brutal. I’m fairly certain kool-aid consists of toxic radiation and sugar. The toxic radiation is purchased in powdered form and my kids add about 3 lbs. of sugar per quart.

They like their radiation sweet.

After grouting one of my showers with SpectraLOCK’s #89 ‘Smoke Grey’ grout I created little grout cakes. Since I wasn’t hungry I decided to test the stain resistance of SpectraLOCK, just because I can. And, because I tell all of my customers that they should choose SpectraLOCK, I should have something to back up my preference rather than the ease of installation – that simply makes my job easier.

Two blocks of SpectraLOCK grout and cherry kool-aidTo the right you will see a photo of two of my grout cakes (I’m gonna copyright that term) and a small bowl of toxic radiation cherry kool-aid. Normally when I place something light colored like that next to a bowl of cherry kool-aid it starts to tremble with fear. SpectraLOCK grout cakes do not tremble – ever. They just sat there with a smirk as if to say ‘yeah, so…?’

Fine – in you go!One block of SpectraLOCK grout soaking in cherry kool-aid

Now, normally it takes about .0314159 seconds for just about anything to permanently stain when placed anywhere in the vicinity of cherry kool-aid, let alone actually soaking in it.

So I carefully calculated the ideal amount of time to leave the grout cake soaking and after a lot of beer thought I decided that to get an overly-realistic sense of how stain-resistant SpectraLOCK actually is I would leave it in there for … two weeks.

Hey, I have a job. I don’t have a lot of time to watch grout soak in kool-aid.

In all of the photos below the cake that was soaked in kool-aid is the one on the left. It’s fairly obvious but I don’t want to be vague.

Block of SpectraLOCK grout after soaking in cherry kool-aid for two weeksSo, after two weeks … I’ve done it! I’ve actually stained SpectraLOCK! Well, I’ve colored it anyway. So to see whether or not it actually stained I needed to try to un-color it. (You can go ahead and copyright that term if you wanna)

To get rid of the pretty pink color I decided to use Oxy-clean, which is available just about everywhere. The active ingredient in Oxy-clean is oxygen bleach and it is great for getting most stains out of most things provided it is only dirty or ‘colored’ like our grout cake up there.

I did not scrub, brush, or otherwise attempt manual cleaning of the grout cake during any of this. I simply mixed some Oxy-clean and water and let the grout cake soak in it for three hours then rinsed it off. After about three hours oxygen bleach basically loses its effectiveness since most of the extra oxygen molecules (which is how it works) are gone. It’s simply water and soda ash at that point.

Block of SpectraLOCK grout after one cleaning

After one soak and rinse

So after one soaking and rinse …

Not quite as red but still a pretty pink hue to the SpectraLOCK. Given that all I did was let it soak for a while and rinse it I find that to be fairly impressive nonetheless.

Block of SpectraLOCK grout after two cleanings

After the second soak and rinse

So I did it again…

That is impressive to me! It tells me that the coloring of the cherry kool-aid (I’m still convinced its toxic radiation) did not actually stain the grout but rather was only sitting on the surface in the pits and dips of the ‘cake’.

Block of SpectraLOCK grout after three cleanings

SpectraLOCK after three soakings and rinses

So I did it one more time…

Yeah, that’s nearly the same color as it started. If you look closely you can still see a very slight pink tinge to the grout cake on the left but for all intents and purposes I believe it to be the original color. And that could probably be eliminated by another one or two soakings or, you know, actually scrubbing it.

Now, in the interest of full disclosure some may think that this is a post about the effectiveness of oxygen bleach. Well, it is that too. But, I will tell you that it does not get cherry kool-aid out of everything – that’s how I know cherry kool-aid is actually toxic radiation. Once something is actually stained the color becomes a part of whatever it has stained – chemically. Oxygen bleach will not remove that. Believe me, I’ve tried.

And before I start getting all the ‘well oxygen bleach IS bleach – duh!’ hate mail – it actually isn’t (bleach). It will not ‘bleach’ the color out of anything, it simply removes dirt and surface stains from stuff. It does this by releasing oxygen molecules when mixed with water which then attach to the stain and released it from whatever you are attempting to clean. It will only do this if it is not actually ‘stained’ but rather only has the stain on the surface. Bleach actually removes the color, oxygen bleach does not. You can use it on your dainty red unmentionables if you want.

So it is my conclusion that yes, SpectraLOCK grout is actually stain resistant – and then some. The claim that SpectraLOCK ‘locks in color and blocks out stains’ isn’t just hype. I’m absolutely certain that if cherry kool-aid will not permanently discolor it after two weeks fully submerged that your kitchen backsplash, entry floor, and shower tile will be nearly bulletproof. I’m absolutely confident that if you clean your tile with any regularity it will continue to look brand new for a very long time.

So now when you see the Laticrete SpectraLOCK advertisement of a tiled floor with a glass of wine spilled on it you now know it isn’t just a marketing ploy – they really did that. And I really did this – with cherry kool-aid.

Because wine isn’t made with toxic radiation.

{ 54 comments… add one }

Leave a Comment

  • Emily

    Hi roger,

    Great blog! Any ideas why my laticrete grout is staining like crazy? my kids spilled pink soda on it and it won’t come out. And the rest of the grout is already discolored from dirt. I tried bleaching it and it’s not helping.

    • Roger

      Hi Emily,

      It’s staining because your kids are spilling pink soda on it. :D What particular laticrete grout do you have? Do you know?

  • The Gunns

    You Sir, are awesome! Lol We’re amateur home renovators, our homes only, and are constantly learning and looking for different, better, more economical ways to do what we need to do. I’ve learned so much in just the Spectralock and Ditra knockoff pages of your site. You manage to blend extensive experience and knowledge, with a wicked sense of humour!! The best combo EVER!!
    Keep putting the knowledge out here, I’ll keep double checking some of our ideas for validity.

    Thanks again

  • Maria

    Hi Roger,
    I loved your experiment! I have a question for you regarding the Spectralock grout. I have about 700 sq. ft. of grey porcelain tile with white grout (about 4 years old). The grout looks completely grey and dirty where the traffic patterns are. Next to the walls it looks perfectly white still. I usually use a Hoover steam cleaner (with just water) to clean the floor. The tiles always look great but the grout never gets clean. What method do you recommend to clean that much grout? I was going to try the Oxy Clean, but any advice on how much to use? Is the only way to do it to use a small brush and scrub and then rinse? Should I seal it after I clean it? Any advice you could give me would be greatly appreciated!

    • Roger

      Hi Maria,

      The oxy clean will work very well on that. You don’t need to use a small brush, you can use a large one. :D It is best to mix it up with water, soak the floor and let it sit for 10 minutes or so, then scrub and rinse. Repeat as necessary. Sealing won’t do much at all with the spectralock, you’ll just have the dirt on top of the sealer rather than on top of the grout. Either way it shouldn’t penetrate the grout. More frequent cleaning would help a lot, the steam cleaner every couple weeks or so would be ideal.

      And yes, I know it’s not an ideal world. :D

      • Maria

        Thanks for the reply Roger. I was really hoping you had an easier way! Oh well! I am one on those people that needs exact recipes for everything. How much oxy and how much water? This job is going to take me forever! I am now wishing I chose the dark colored grout!

        • Roger

          Read the back of the bucket. Typical mixture. You may also try to have it professionally steam cleaned, that may get it back to where you want it.

  • Gerard

    Hi Roger,

    Can you or should you seal Spectralock to minimize the cleaning process in a shower for example. Will it ease the process or is it essentially useless to seal it (and what would be the best product to seal it whit?)

    You are hilariously funny.


    • Roger

      Hi Gerard,

      No need to seal it at all. I couldn’t stain that stuff with frickin’ kool-aid, pretty sure it’s fairly easy to clean with normal filth. :D My filth is far from normal, I try to destroy things.

  • GK

    Great site, I have learned a lot from it.
    I am about to use spectralock on my newly tiled shower that consists of 12×12 tiles with a glass mosaic insert.
    I was reading the spectralock instructions and it says that it is a sanded grout. Have you ever had issues with it scratching the glass tiles?
    sorry if it has already been asked. The search brought up nothing.

    • Roger

      Hi GK,

      Never once, and I’ve used it on a LOT of glass. That does not mean it won’t, it just means it’s never done it on any I’ve used it on. You always want to test it first to make sure, but you should be fine. It’s not actually ‘sand’, as is the normal definition, it’s a colored aggregate bead.

  • DOUG

    Hi Roger,
    I’m new to epoxy grout. I’ve been looking at Spectralock. But what is the difference between Spectralock, Spectralock Pro, and Spectralock Pro Premium? Any tips for using epoxy grout?

    Thank you,

    • Roger

      Hey Doug,

      Spectralock is the regular consumer version, it’s nearly identical to the pro version. If you don’t work with it often you’ll never notice the difference. Specralock pro premium is just the second generation of the pro version, it will replace the spectralock pro. If you use spectralock just follow the time limits and directions on the packaging, it’s extremely accurate. Just take your time and be diligent about the cleanup.

  • Joel

    “Now, normally it takes about .0314159 seconds for just about anything to permanently stain when placed anywhere in the vicinity of cherry kool-aid”

    nice reference to Pi/100 :wink:

    • Roger

      You know you’re the first person to ever point that out? :D

      I actually used to be a physicist (still am, technically I guess), old habits and all that…

    • Alex Santa-Pinter

      Cool… I’m not the only one “seeing” these things! ;)
      Now, I need to go get myself an adult beverage.

  • Ed

    Hey Roger,

    What do you recommend for cleaning Spectralock and porcelain tile once it’s installed?


    • Roger

      Hi Ed,

      Any tile-specific neutral ph cleaner will work fine. Not a general bathroom cleaner – those are often abrasive. But any tile specific cleaner works well.

  • Amrita

    What a grand experiment you did! I’m getting ready to have tile countertops installed in my kitchen and this grout sounds great. Can you tell me what the fumes are like while its being worked and curing? I have multiple chemical sensitivity and products that emit VOCs, solvent fumes, fragrance chemicals, etc. are a problem. Just wondering if I could use it, or how long it would take to become inert and fume-free.

    • Roger

      Hi Amrita,

      The total VOC Content pounds/gallon (grams/liter) of Spectralock in unused form is 0.00026 lb/gal (0.031 g/l). It smells a little funny as you’re working with it but it isn’t an odor that I find annoying – that may just be me, though. :D After about 12 hours you can’t smell it at all. The ability to use it is dependent on your particular sensitivities. Once it’s cured it’s essentially plastic, so it shouldn’t be a problem.

      • Amrita

        Thanks, Roger. Sounds like the fumes aren’t as bad as the old epoxy grouts.

        • Roger

          Not. Even. Close.

          I used to look like Darth Vader when I installed epoxy with all the respirators and such – nothing buy kneepads now. Much, much better.

  • Scott

    Hi Roger

       I want to use Laticrete SpectraLOCK PRO Premium Epoxy Grout in my new shower will I have any problems with saging on the wall and also will it work on the celing? 


    • Roger

      Hey Scott,

      It will work just fine on both. It may sag a bit for the first ten minutes or so after mixing, after that it won’t.

  • Heidi

    floor elf you are wickedly funny…
    and you need your own cable show!
    thanks for the chuckles and the grout info
    some girl.

    • Roger

      Hey some girl,

      Thanks! You rock! :rockon:

  • mountain eagle

    So……………. how do you feel about Starquartz, StarGlass? :D

    • Roger

      Not as good as SpectraLOCK! :D

      It’s good grout. I don’t care for the way it works, I’m just used to the stuff I use. Doesn’t mean it’s no good – it is, just means I’m a grumpy old bastard who likes the stuff he’s used to. I’ve used the starquartz a couple of times and it came out consistent and clean. Dunno how it stands up to kool-aid, though. :D

      • Colleen

        “Dunno how it stands up to kool-aid, though.”

        Which is exactly why you should’ve done an additional cake of some other kind of grout. Just imagine how impressive the SpectraLOCK would look then!

        It’s not like you have anything else to do, including extinguishing your dog.

        • Roger

          But my dog doesn’t like fire… :D

  • lee

    hi , great posts–
    grout types..I’m worried about expansion .strong floor 1320, 1.25 ply, going with 1/8 ditra [height issue]- travertine unfilled and tumbled, four sizes 16 x 20—to–6 x 6 in pattern, Floor is almost exact minimum for expansion 26′. Is there a grout I could use to help with expansion? never played with epoxy . would it help to tape plywood substrate seams? or if
    I had to, would it help to go with standard height ditra? room does get evening sun
    ..I used to think expansion problems meant you had to take a little blue pill..
    thanks, lee

    • Roger

      Hey Lee,

      Sounds like you have more than enough deflection and a decent substrate for your floor so you should be just fine with the regular ditra and making SURE you leave at least 1/8″ gap around the perimeter for expansion. Epoxy would probably be your best bet but short of that you can always use a highly modified thinset which will assist with any movement.

      I think as long as you leave the perimeter gaps, use a good modified thinset (like mapei ultraflex II) you can use regular grout and forego the soft joints. Taping and mudding the plywood seams won’t make any difference – installing the ditra essentially does that anyway.

  • Tony

    Ever use the TruColor pre-mixed grout from Bostik? Did a shower last summer using this stuff. Never used it before so followed the instructions to a tee. Homeowner started having some issues that sounded like the grout was washing out in spots. He added grout to small spots that had pitted and it never improved (I think partly because the new grout never had a chance to set up). Anyway today I removed all the grout on the floor, much of which came out relatively easy, like wet sand. Going to re-grout tomorrow with traditional grout. The grout on the shower walls and bathroom floor still look great and solid, but the shower floor was spotty at best. The grout had a full week to set up before the shower was put into service but it just seemed like it never really dried. Any comments?

    • Roger

      Hey Tony,

      That is specifically the reason I don’t use anything pre-mixed. (I used to – don’t feel bad :D ). I look at it like this: Anything that is pre-mixed requires air to cure (otherwise it wouldn’t stay usable in the bucket). More often than not if you add water back into the cured product it will, in some form or another, re-emulsify. It is simply unstable in my opinion.

      I have never used the pre-mixed grout – only because I stopped using mastic before they came out with it. I explain mastic to people like this: If you put the lid back on the bucket that product stays usable for months (years). A 12×12 tile is larger than the lid to the bucket. Placing a tile on a wall over mastic is just like putting the lid back on the bucket – it will never fully cure. When they came out with the pre-mixed grout I figured it would have the same problem in wet areas like showers. I don’t trust anything that doesn’t cure through an entirely chemical process like portland cement-based products.

      It may work fine in things like the floor you mentioned – I simply don’t know and am unwilling to find out. Cement-based or epoxy grouts for me. I’d tell them to keep an eye on the shower walls, I don’t know what it’s going to do. Probably not anything but I’m paranoid like that. :D

  • Mike

    Hey Roger, I’m back! I am having a hell of a time with this floor! I was going to put the Warm Wire down and then SLC over it, but Watts Radiant says not to put the wire directly on there because I have a bunch of cutback residue. So they suggest a skim coat of thinset, then the Warm Wire, but according to Laticrete and Custom, I can’t pour SLC over a skim coat of thinset, HELP! I don’t know what to do at this point. Right now I have a slab with cutback on it, I’ve gotten what I can up from it with a grinder. I have the Warm Wire to put in and I wanted to level it, but I don’t know what to do now. Thanks for any help you can provide, I do appreciate it.


    • Roger

      Hey Mike,

      How about just using a skim coat of the SLC? Just mix up enough of it to give you a good skim coat for the cutback and trowel it on there – doesn’t need to be level, just gives you a base coat. Make sure you use an SLC primer on that concrete! That will guarantee that it sticks.

      • Mike

        Thanks Roger! Since I wrote you I’ve checked the floor a good amount, it’s pretty flat and level so I’m thinking maybe just a skim coat of thinset to give me a separation from the cutback for the Warm Wire and then the Warm Wire and Tile. I think the main reason I was wanting to use an SLC was so I wouldn’t have to tile right over the Warm Wire, but a skim coat of a good thinset, Flexbond probably, will give me a better bond over the cutback than the Level Quick right? I am thinking that because there are some spots where water doesn’t penetrate, and some thinsets say it doesn’t matter, like the Laticrete Gold and Platinum. Thanks again Roger, I really appreciate your time.

  • Mike

    Hey Roger, so I’m finally ready to do my installation in my kitchen, comments below concerning that. I have changed up my plan and wanted to hit you up for some more of your expertise if you don’t mind! My plan is simply, WarmWire on the slab, SLC, and flagstone tile. My questions are, have you ever had to attach the WarmWire straps to a slab, I would guess I just use a hammer drill and try to screw them down. And, would you suggest an underlayment on the slab such as easymat or something? I am trying to avoid that, but if it’s something that is imperative I want to do it right. I do understand that doing the WarmWire directly on the slab will result in heat loss, but that is a calculated measure I am taking when weighed against a bunch of other factors. Thanks Roger!

    • Roger

      Hey Mike,

      You can attach the strips for the warmwire with either construction adhesive or, better yet, some of that spray adhesive from 3M. With either method make sure you use the primer for the SLC so that it will adhere to the places you may have gotten the adhesive on the concrete. Trying to screw them down is just gonna piss you off. :D

      I always suggest an underlayment over any substrate. Easymat is fine but I prefer (and I’m sure you know this :D ) Ditra for floor tile. Not particularly necessary with the SLC if you don’t want to do it but you need to make sure that you carry the expansion joints in the concrete through to the tile installation and caulk that grout line rather that filling it with grout. Carry it through the SLC also if you don’t use ditra.

  • Mike

    Apparently I’ve developed an allergy to SpectraLOCK now!! Though I still swear by it. I was dreading finishing up the grout on my shower ceiling since I now know I am allergic, and sure enough, red rash on my arms and my eyes are all puffed up, and it lasts for days too! Still great stuff, I have one more floor to do, might have to get my buddy to grout it for me.

    • Roger

      Great, something else I have to worry about – thanks! :D That really sucks Mike, sorry to hear that. It may be a reaction to the part ‘B’ of the epoxy mix – a lot of people have problems with it but it’s usually only a redness that develops when it contacts bare skin – never heard of any eye problems.

  • sandy

    Chuck the cupcakes in the dishwasher….

    • Roger

      Hi there Sandy,

      I would have loved to! That, however, involves the super secret ninja skill of sneaking whatever jackass idea I have that week past my wife and into her dishwasher – that ain’t happening. Could you imagine giving someone like me free reign over all your kitchen appliances? See – that’s what I mean. She guards those damn things like the Hope Diamond.

      For everyone else – Sandy up there is a mosaic artist. You can check out her stuff by clicking on her name in her comment. She also looks as if she’d be fun to party with – that’s always a plus! However, that would also require the aforementioned super secret ninja skill – and I don’t live in Brisbane. Check out her stuff anyway (the mosaics).

      • sandy

        Roger the cement dodger it sounds! Well, I know what you mean……Dave, hubby, now cooks and does a lot of things I hate to do as I am too busy to cook!!!! My secret tip is to always be covered, well at least some body parts, (hands, feet) etc with Midnight Black thinset or grout. It looks dreadful if you make a sandwich and leave fingerprints on it. Only had to do that a few times and the crunchy stuff inthe vegemite sandwich taught the men in this family to get their own! Re ironing, I left lovely black fingerprints on the white t-shirts and that was that!

        I use every kitchen utensil in my mosaic studio and even have put things in the oven…..I am always experimenting with Laticrete products…doing naughty things to them that really work in mosaic art! Like Madonna, I like to make the thinset into art that oozes over the tiles (ie wear your underwear on the side, so to speak!).

        Last week we put glow in the dark grout under clear glass gems in a 2 metre whale “spurting” for a swimming pool mural, and in the moonlight it glows and glows….very, very beautiful – a fantastic work in progress by a student of mine. In the cold of Brisbane’s freezing winters (as if!!!) she has to swim, SWIM!!!!!!!!!! across to the sheer pool wall that drops straight into the pool and apply mosaics made on mesh. Much discussion has gone into how to do this, from epoxy to rapid bla bla bla….but imagine in a wet suit, swimming over with a raft, climbing on a plank and trying to apply mesh mosaics! It would win a prize I think in a funny video show, except she is fair dinkum, and the wall is over 40 odd metres long and 2 metres hight. We breed mosaic addicts “tought” downunder!
        I love epoxy grout and my glowing cup cakes look very scrumptious and great for Weight Watchers! Just finished a mosaic workshop here and 6 more die-hard Laticrete artists for life. We teach kids in school from Grade 1 how to use thinset etc. Imagine littlies going home and demanding the correct professional products! Makes my day.

        We mix a lot of joy and madness into our mosaics, always knowing the products and the people behind the products are perfect in every way.

        I thought dishwashers were for testing things out….Your wife and my husband would be awful together, they would have the place bolted down! LOL!

        You sound so much fun and keep it coming! Thanks – cheers from Brisbane….glorious Brisbane….



    Somehow you manage to make science hilarious, a skill that is far too rare in the world today – keep up the good work :)

    In my five year tenure at LATICRETE I’ve seen countless demonstrations of SPECTRALOCK being subjected to all kinds of horrible compounds only to bounce right back to the original color – I can honestly say this is the first time I’ve seen anyone try it with Kool Aid!


    • Roger

      Well Hi there Ken! Thanks for the kind words.

      Making science hilarious is the only way I get my kids and people that couldn’t care less about stuff like epoxy grout interested in it. I appreciate you taking the time to read through my ridiculousness – it proves once again what a top-notch company Laticrete is!

      You guys keep up the good work – I’ll just keep up the jackassery. :D

  • Mike

    Hi Roger, great site. I am rehabbing my new house after gutting it to the studs. I discovered SpectraLOCK before doing the first tile job in my bathroom. Pricey stuff but I swear by it as well! In my bathroom though I used a white SpectraLOCK and with all the stuff going on around the house I wasn’t able to allow it to cure completely before electricians getting in there. It seems some of it got a little darkened, but I haven’t tried Oxy on it yet. My wife swears by that stuff so we’ve got plenty around.

    Anyway, I do have a few questions for you if you wouldn’t mind! I just finished up a hardwood floor installation and from the floor there is a step up to a small landing, which I covered in hardwood, then another step up to a small (about 3×5) foyer where the front door is. My plan is to run a piece of the hardwood stairnose allong the step on the foyer, and cover the foyer in slate, butting up to the stairnose. My question is, would you use grout between the slate and the stairnose piece or a color match caulk? My instinct would say caulk. And what about the use of one of those Schluter finish edge pieces?

    The other area I am going to hit up soon is the kitchen. Right now it is a concrete slab. It is not entirely clean as I had to grind off a layer of tar that was holding down the ’50’s parquet flooring. My plan was to shoot down 3/4 ply, then Durock to that, radiant heat and tile. I would prefer to not have to shoot down the ply, but feel it is needed because the slab is not completely clean, and I think it would be impossible to get it cleaned up enough for a self leveler. How would you do this installation, does my plan sound about right? Also, I know you use the Warm Wire for radiant heat, is there a reason you like that as opposed to the mats? I used the mats in the bathroom and they were easy and work great. Just seems like the Warm Wire is a lot of extra work for the same outcome, is it a lot cheaper or something?

    Finally, in my shower I used QuickShelf for my niches. They worked and look awesome. I’m sure you’ve seen them before, http://www.quickshelf.net/order.php. Sorry for the long winded e-mail! Thanks for your time, and website.


    • Roger

      Hey Mike,

      Oxyclean should be able to take that out of your grout without too much of a problem. Just let it soak and rinse it off really well.

      If you use hardwood stairnose use the color-matched caulk. It will allow flex in there and grout will not. If, however, you are using spectralock you can use it if you want to. The micromovements will not cause the epoxy to crack out as it will with cementious grouts. If you have a lot of humidity and weather changes where you are, though, use caulk. Laticrete makes Latisil which matches the grout exactly and it’s silicone rather than acrylic – more flex when needed.

      Schluter does make a stairnose and they look awesome! They’re expensive as hell, though. :D

      On your slab you can grind off as much as you can and go over the entire floor with a primer made for the SLC. You should be able to find that wherever you buy SLC or somewhere online. Just like priming a wall before painting. It will give your SLC a solid surface to grab and you will be just fine with it. As long as the PRIMER has a rough surface to stick to it will work fine.

      I actually use both the mats and the wires. The wires are cheaper but do take a hell of a lot more labor. I used the wire for that post simply because it shows how to do it with wire and, if someone is using the mats, the post is still relevant – all the information is still there. If I’d done the post with the mats I would get 72 questions a day about how to do it with the wire, knowwhatimean? :D

      I’ve seen the Quickshelf, just never used ’em. I guess I just prefer to build my niches to the absolute size I need. I used to use pre-built shelves and constantly ran into problems with placement, sizing, etc. Building them from scratch solved every one of those problems and actually saves me time. For DIY’ers, though, the pre-built are nice.

      • Mike

        Thanks for the reply Roger. I have used the SLC a few times on three different areas and am familiar with the primer, I’m just not sure how clean the slab needs to be in order for those to work well. I have already rented a slab grinder and gotten up all thats going to come up from it. Also, after my last post I remembered the main reason I had planned to use 3/4 ply. There is going to be an island in the middle of the kitchen and in order to run the electric to it, we were going to lay the conduit down and lay the 3/4 ply up to it on either side, bridging any gap with mortar. Do you have any advice or things to look out for with this type of installation? The Quick shelves worked great for me because I was building the bathroom from the scratch so when I framed the walls I factored the shelf sizes into the framing and was just able to nail them in and go. I used a lot of those Shcluter finish edges in my shower install, they are sharp looking! It started out as just using it for the reveal on the 2 sides, and the ceiling, then I decided to run it on the top and bottom of my accent tile stripe through the middle of the shower and I actually framed out my 4 niches with them as well, instead of using bullnose, cut them at 45’s in 4 pieces to make the square, looks awesome!

        • Roger

          If you need to put down the ply I would put thinset beneath the sheets before shooting them down. This will ensure you have no voids, and in turn ‘bounce’, under your ply.

          If you have used a slab grinder and gotten everything that is going to come off it is clean enough. As long as you use the primer the SLC will be solid and will adhere to the subfloor just fine.

          If you do the ply make sure you fill the conduit channels really well, pack it in there. You want it as solid as the slab – no movement.

          I really like the Schluter profiles, they are very versatile and do look sharp as accents in a shower as you’ve described.

          • Mike

            Cool, sounds good Roger. You’ve given me a little more confidence in going right on the slab. It is what I’d prefer to do.

  • Goldy

    That was great! I love your experiment. I am laughing my head off. :lol2: By the grace of God, I’ve managed to keep kool-aid radiation out of my house (mostly). You are one great humor writer.

    In all fairness, I think you should have ran a comparison experiment with some regular grout cakes. For the uneducated like myself, I laughed & said wow, but maybe regular grout would not stain either.

    • Roger

      Hey Goldy, thanks.

      You’re right, I will do that with some regular grout when I get some time to do so. This is stuff I don’t think about because, well, I stare at this stuff all day. I guess it would drive the point home more with a comparison of regular cementious grout.

      You have to understand that when I’m standing there with two grout cakes, a bowl of cherry radiation and an evil gleam in my eye I’m not exactly thinking things through. :D

      Thanks, when I get some time I’ll radiate some regular grout. Just playing around. :evilb: