Spectralock Pro PremiumAnyone who reads my blog (and lets be honest – who doesn’t?) knows that I am a diehard SpectraLOCK junkie. For those who don’t know what that is, SpectraLOCK is an epoxy grout made by Laticrete. It is stain-proof, pet-proof, and bullet-proof! (Don’t try that, it’ll really piss off the wife…) If you don’t know any of that – you need to read my blog more! :guedo: So just like everything I love – it changed.

Laticrete has recently come out with SpectraLOCK Pro Premium grout. A little birdie told me that this will replace the SpectraLOCK pro grout in the near future. Given that, I need to figure out how to use it – because it works differently than the stuff I’m used to. The difference in the workability may very well be due to the temperature, humidity, hangover flu bug, or any number of factors on the particular days I was working with it.

But it just doesn’t feel ‘normal’ to me – you know? It seems like it tightens up (gets stiff) and starts to roll out of the grout joints more quickly than the other stuff did. So, as with any installation product, if it begins to cure faster than you can use it you should just mix up smaller batches. And being the awesome DIY crowd you are – it’s probably a good idea for you to know how to do that anyway. So this is the best way I’ve found to do it.

A few basics first: SpectraLOCK is sold in different unit sizes. The base unit is called … wait for it … a FULL unit! Wait, where you goin’? This isn’t complicated like the metric system or anything, stick around. There is also the COMMERCIAL unit, which is what I buy (and you likely will not need) and it contains four full units. There is also the MINI unit – this is 1/4 of a full unit.

So: 1 commercial unit = 4 full units and 1 full unit = 4 mini units. Now, you can split up whatever you feel comfortable with, I split the full units into mini units. And this is what I’m about to show you. However, if you feel the need to split them into smaller units, or split the mini units into smaller units you can do that as well, you’ll just need to change the measurements.

When you break down the components into smaller units you need to do it by weight. I don’t see why splitting the liquids down by volume would be significantly different – but I was always told to break them down by weight. So do that. Really.

SpectraLOCK has three components, the part A and part B liquids and the part C powder. The part A is the yellow stuff in the foil bag, part B is the white stuff. Part C powder is in the carton. For this I’ll be splitting up one full unit so the bags and carton may look larger than what you have – mine’s bigger! :dance:

You want to have a scale (scrape off the *ahem* ‘illegal substances’) and some one-quart ziploc baggies (the unused ones). For a full unit you’ll want to split each liquid into four baggies. Each liquid baggie weighs a different amount! So don’t just go puttin’ the same amount of everything in all the bags, it won’t work, you’ll have 1/2lb. of the white liquid left – then whaddya gonna do?

  • Part A (foil bag) has 5 ounces of liquid in each baggie (4 baggies)
  • Part B (white liquid) has 5.2 ounces in each baggie (4 baggies)
  • Part C (powder) has 2.25 pounds in each baggie – or whatever you choose to dump it into (4 of ’em)

Just measure out all those components and zip them up. Once you’re done with that you’re ready to mix smaller batches in workable sizes. I just measure out the powder as I go along – I’m a rebel like that. 8)

AGAIN! If you have smaller units or want smaller batches you’ll have smaller measurements. You just need to weigh out what you have and split them into equal parts.

The photo above shows one full unit in the back, the two large bags and the carton, and one of the smaller units after I’ve measured them out, the two small baggies and the cup of powder. The amounts in the baggies and the cup is what you’ll be working with at one time.

To mix them just get yourself a nice clean container (scrub the beer coffee rings out of it) and add the two liquids together. Just roll up the baggie from the zipper side down until you have no room left to roll (like toothpaste) and snip off the corner of it with scissors. You can then squeeze all the liquid out of it with a minimum of mess.

Snip off the end of the bagSqueeze it out like toothpasteSnip off the tipSqueeze it out like toothpaste


Once you get those in there YOU NEED TO MIX THE LIQUID TOGETHER! Do that before adding the powder, or it’s gonna be one big mess you don’t wanna deal with – take my word on that. :D

MIx the liquids together before adding powder!MIx the liquids together before adding powder!


Once you get your liquids mixed together you can add the powder. Add about 75% of the powder first and mix it all up. Get a nice, smooth consistency, then you can add the rest of the powder. This helps get everything mixed evenly whereas if you dump it all in there and mix it you’ll spend more time getting an even mixture.

(Jesus, did I just type ‘whereas’??? I need a beer nap…)

Add about 75 percent of the powderMIx it up well
Then add the rest of the powder and MIx it up well

Here's your grout - get to it! Quickly, damnit!

And that’s it. It’s all ready to go. When you grout, fill your grout lines and begin washing the tile in about 10-15 minutes. In another 40 minutes or so you can begin the second wash. I’ve noticed with the new stuff that you’ll only have about 35-45 minutes of what I consider ‘workable’ time. It’s not like it turns into a rock after 40 minutes, but it does become considerably more difficult to work with.

If you keep your batches small enough to install in that time frame it won’t be a problem – it’s when you go past the viable working time that it starts becoming difficult.

While I have voiced my displeasure with the new mix in a place or two, after I calmed down and sobered up thought about it I realized that SpectraLOCK is still the easiest epoxy grout on the market to work with. That, coupled with the rock solid (pun intended) color match you get from it, SpectraLOCK will still be my epoxy grout of choice.

I just need to quit being such a hard-headed bastard and learn to work with it a bit differently. One of the key factors in doing that is to keep the mixes in manageable batches. Just take your time, a little extra now will go a long way toward the long-term durability of your tile installation. And it WILL be stain-proof!

Here’s some basic information about the new stuff from Laticrete: Laticrete SpectraLOCK Pro Premium

And here’s a chart for coverage to see exactly how much you’ll need: Laticrete Grout Coverage Calculator

As always if you have any questions at all feel free to post them below. I’ll answer them once I sober up get home from work.

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  • Thomas Aquilina

    Ok I have an installer making a bid and I told him I bought spectralock pro… he say ok for floor but not steam shower walls or ceiling he says it will make a mess. (Gravity and all, you know!)
    So, is it poosible to do a decent installation with spectralock pro? He suggests spectralock 1, and says that doesn’t have the same issues of epoxy grout and is a lot less messy. Any thoughts on wall and ceiling grouting with spectralock?

    • Roger

      Hi Thomas,

      It will only make a mess if the installer doesn’t know how to properly install it. Once cured it isn’t going to do anything.
      I do not know if spectralock one is approved for steam showers or not. Give schluter a call and ask them.
      It will do NO good to tell him what I said in the first sentence. If he doesn’t know how to use it properly then telling him that’s why it’s a mess isn’t going to teach him how to do it properly. :D

  • Laura

    Do you have any experience with spectralock 1? We will be tiling a steam shower soon and someone suggested the premixed spectralock.

    • Roger

      Hi Laura,

      I have used it, but I do not recall whether or not is is approved for use in steam showers. I would think so, however(!), CALL LATICRETE FIRST AND ASK. 1.800.243.4788 x1219

  • Nick Avery

    Have you ever used the Spectralock Epoxy grout in a grout bag? I realize it would destroy the bag but just wondering if it would lessen the cleanup?
    Thanks in advance.

    • Roger

      Hi Nick,

      No I haven’t. It will be cleaner going in (and a hell of a lot more time consuming) but I really don’t see how it will save you much, if any, on the cleanup side. Once you wipe it’s gonna go over the face of the tile anyway.

      • Nick Avery

        Thank you Roger.

  • Felice L Robinson

    May you please comment on how I find a professional in Dc, Maryland, Northern Va area who knows how to use this stuff?

    • Roger

      Hi Felice,

      About the only way is to call whichever ones you choose and ask them what brand of epoxy grout they prefer. If they know how to use it spectralock will be their first answer.

  • Kevin McGreevy

    Hey Roger.
    Just noticed something. Look at the quantities loaded into the baggies. MDS shows 600g (21.16oz) of Part-A and Part-B,. So, 150g (5.3oz) into each. The unbalanced recipe of 5 and 5.2 oz above may be what is causing it to kick more quickly than the MDS working time. I’m fortunate that I have an accurate refrigerant scale. So, I just get 150 grams of A&B product mixed with the 1.021kg (2.25) lbs of part-c. However, I did notice in the MDS that Laticrete’s math doesn’t quite work out between the mini and full units either.
    For really small batches, you will need about 3.4g (.12oz) of Part-C for every gram of combined A and B which should keep the color spot on!

  • Mitzi Howard

    Do you have any experience with the Laticrete translucent grouts: SpectraLock Pro Premium Translucent Grout or the Plasma ready to use?

    I’m have a big project done with all glass tiles and the translucent aspect really appeals to me, but I can’t find any reviews or information about either of these products.


    • Roger

      Hi Mitzi,

      Sorry, I have no experience with those. They are fairly new to the market. I have heard good things about them in pro circles, but haven’t used them personally.

  • Nolan

    Anyone had issues with specktraLOCK grout not matching itself?! I’ve used it on multiple rooms and never had a problem, but recently I grouted a large hallway, I had to do it in sections (which I’ve done before with no problem) by myself so I use a mini unit each time I grout. For some reason, even though I used mini units from the same full unit, the color isn’t matching up. Half the hallway is much lighter than the other half. Not sure why this happened or if there’s anything I can do about it!

    • Roger

      Hi Nolan,

      I have never had that issue. I’m assuming you used similar techniques when installing the separate batches? (amount of water, time, etc.) I would give Laticrete tech a call at 1.800.243.4788 x1235.

      • Nolan

        Hey Roger,

        Thanks for the response. I did indeed use the same frantic cleaning technique that I always use with the same amount of water/cleaning solution.

        I then contacted laticrete and they said every so often there’s a discrepancy between the sand (one wasn’t dyed as dark as the other…?). In this case it was about 2 shades lighter so they are sending a stain that will darken it. Not ideal but not much I can do about it now except hope the stain matches it. It’s really not noticeable unless YOU LOOK AT!!! Haha.

        Thanks again,


  • ben

    Seems like a big “Scare” component is the epoxy getting and setting on tile. Couldn’t I just use painters tape to hug the tile edges, and also tape a piece of visqueen to cover the tile so that the only thing exposed are the grout lines? I know it would be labor intensive, but on 12×24 tiles it seems the prep time would still be shorter than all the clean up – and avoids risk of grout on the tile surface?

    • Roger

      Hi Ben,

      It *would* work, but simply following the instructions to the letter is MUCH easier. :)

  • Josh

    I have used Spectralock Pro with great success on glazed ceramic tiles. It is pretty easy to work with as long as you clean it up properly. How would you grout porous brick tiles with this stuff though?

    • Roger

      Hi Josh,

      You can either use a grout bag to install the grout, or install a grout-release over the brick first.

      • Josh

        If I don’t use a grout bag, after I use the grout release, do I just grout like normal? Also, do you recommend a pre-mixed grout or epoxy? I am worried about color consistency since I won’t be able to finish this in one day. Thanks!

        • Roger

          Yes, you just grout as normal. With brick, if you don’t want to use a powdered grout (TEC power grout is extremely consistent) I would use a single component (pre-mixed) grout. I would absolutely not use epoxy on that. It’s way too porous and once epoxy cures you’ll NEVER get it off of anything you don’t want it on.

  • shaun

    You say to clean up 10-15 minutes after grout is installed. Is that 10-15 minutes after you start or after the 30 min you spend installing it? I have read a lot and am using this on my new shower and it seems like most people spend about 30 min grouting then start clean up a few min after that.

    • Roger

      Hi Shaun,

      With spectralock it is 10-15 minutes after you start – so you need to only do as much as you can have done in that time frame. With regular grout the 30 minute thing is fine, with epoxy it is not.

  • Ryan

    What are your thoughts on single component grouts, such as Custom’s Fusion Pro? I have a living room floor that I am tiling, and the grout is going to be in a light color, and really want to minimize issues later on down the road.

    • Roger

      Hi Ryan,

      The modern single component grouts are absolutely awesome! Fusion pro is a great grout and extremely durable. If you have the option to use one – do it.

      • James

        Roger will a single component grout like this not stain and change color over time like an epoxy grout?

        Thank you

        • Roger

          Hi James,

          To my knowledge they will not, they are all UV stable, which is what causes the color change in some epoxies.

  • Cassius Hartl

    Someone may have already said this, but breaking down by weight is much more accurate than volume, especially for those that aren’t in a chemistry lab. And you don’t want all that epoxy resin on your wife’s measuring cups.

    Most kitchen scales are accurate within 1 gram. For example, 1 gram of water is equivalent to 1 ml (1/5 teaspoon), but measuring 1/5th of a teaspoon is difficult for most of us.

    Love the site, thanks for the infos.

  • Freeman

    So I am easliy and unfortunately still confused regarding sealing. Do you do or do you don’t need to seal Spectralcok Pro Premium grout. I appreciate all your guides, books and help you provide us tileamateurs.

    • Roger

      Hi Freeman,

      No, you do not need to seal spectralock grout. No epoxy grout requires sealing.

  • Claude

    Hey, great site!

    I’m the owner of a little building that contains a very busy restaurant. The floor is textured 6 x 6 quarry tile over concrete. The problem is that after 10 years the grout in certain locations has all but eroded away. I was thinking to regrout using Spectralock but I’ve not used it and am nervous.


    1) Can I go over and up to the existing (solid) cementious grout?

    2) Should the floor be 100% dry?

    3) I have 3 spots, 1 @ 9’ x 3’, 1 @ 3’ x 3’, 1 @ 2’ x 2’. How much should I mix at a time?

    • Roger

      Hi Claude,

      The biggest issue for restaurant grout is actually the harshness of the cleaning products. Rather than regular spectralock you may want to use spectralock2000, it’s a commercial grout made for that purpose.

      1. No, it needs to be removed to at least 2/3 the depth of the tile.
      2. While installing new grout, yes.
      3. Probably 1/2 of a unit until you’re comfortable working with it.

  • Ed Sabedra

    Thanks for a great site for DIY folks like myself. My question is how to apply Spectral Pro Premium epoxy grout on a ceiling? Also where to buy it?
    Thanks for all your humorous help!

    • Roger

      Hi Ed,

      Very little at a time. You can also hold back about 10% of the powder when you mix it. You may need to order it online. Contractor’s Direct is where I get it.

  • Adrian

    Hi I asked my contractor to use epoxy grout in my steam shower, I guess the installers might not have had much experience. The first problem was the grout haze, very rough and smeared on white subway tile. So for three days random cleaners used acetone and finally a epoxy haze remover. I don’t think rinsing was being done. My white floors are now stained from standing on a cardboard box top and spilling chemical in it. Ther are boot indentations too. The contractor asked installer to put more expoxy grout on floor. Installer is trying to use regular grout.. what is best solution?

    • Roger

      Hi Adrian,

      Best solution is to get that installer out of your damn house! Whoever your contractor is you need to sit down with them and explain that you feel there has been sub-par work from the point the grout was installed and he apparently used inexperienced ‘installers’, and that his ‘solutions’ have led to more problems than they’ve solved. Lay out exactly what you expect to happen – clean, new tile – and that you’ll accept nothing less.

      I’m assuming you’ve paid good money for the installation, as well as a premium for epoxy. There’s a reason professionals charge a shitload to install things like epoxy grout, it’s a specialized skill that, when done incorrectly, can go sideways quickly. When it does we are responsible for it. It went sideways, now they are trying to solve the problem without (obviously) adequate knowledge. Ask them how they are going to solve it and get definitive answers before they do anything else to your house.

  • Laura Rusick

    Hi, first just want to give a big shout-out for your directions and your reply to an earlier question! We finally got our backsplash and shower walls complete, and we think they look great (pics too big to attach)! While this is a bit of a pain to use, so so happy there is pretty much zero maintenance. Well worth it.

    One question – we (finally) got around to replacing the crappy old wood thresholds with the same tile we used for our backsplash and shower wall accents. Went to grout today and no clean up packets left!! Any recommendations on either where to get some, or what we could use instead?

    • Roger

      Hi Laura,

      You can use powdered dishwashing soap, like cascade. While not as effective you can also use laundry detergent like tide, but you need to rinse that off REALLY well or you’ll get a white film.

  • Eric

    First time using Spectralock grout. The walls are a PITA. The grout does not want to hold on the wall. Just as much on my drop cloth as the wall. Should I add less colorant to get a looser mix? What am I missing?

    • Roger

      Hi Eric,

      You can omit up to about 10% of the sand, if that makes it easier for you.

      And yes, I realize this reply is too late, but the info will be here for others in the future. Sorry for the delay.

  • Eric Woollen

    I accidentally froze parts a b and c of my Spectralock pro premium grout. I had not yet mixed parts a and b. Have I ruined my grout? I can see through the clear plastic bag that part b has sort of separated into white and clear liquids. This is a whole full unit so I’m hopeful that it can still be used.

    • Roger

      Hi Eric,

      If it froze then do not use it. That’s what I’ve been told, so I never did do it. I honestly don’t know if it will work or not. Provided it cures fully it should be fine (if you did use it).

      And yes, I realize this reply is likely too late, but the info will be here for others in the future. Sorry for the delay.

  • Eric Woollen

    I put parts a b and c in the freezer before getting to work to extend the working time (prior to mixing). I meant to take it out prior to actually freezing it but I decided last minute to wait for the next day and it got left in the freezer overnight. I’m worried about parts a and b because the instructions say do not freeze. Also, looking at part b through the clear plastic bag now that it has thawed, it looks like it has separated into clear and white liquids. Have I ruined my grout?

    • Roger

      The freezer thing only works once the two parts are mixed, that’s when heat is created and cold slows down the curing process. It makes no difference at all if you do it before the two parts are mixed (in regards to slowing it down).