One of the most asked questions by do-it-yourselfer’s is whether they should use caulk or grout in the corners. Industry standards state that a flexible material be used at all changes of plane. But! – if you ask a hundred different professionals you will more than likely receive fifty of each answer.  While there are pros and cons of each, I am in the camp that uses caulk. That being the case, I will discuss using grout first. I’m backwards like that.

Using Grout at Changes of Plane

While the phrase “changes of plane” may sound a bit uppity or technical – it’s not. It simply describes the corner or edge of any surface that changes direction such as a corner, a wall to a floor, or a wall to the tub edge. Many professionals simply grout that corner as they do any other space between the tiles. There are a couple of things that must be taken into consideration before choosing this method.

  1. Your walls and the framing of your shower must be absolutely rock solid. I do mean absolutely. Grout is a cement-based product and as such is not meant to flex. If your wall moves your grout will eventually crack – it’s that simple.
  2. The space between the tiles at the change of plane must be large enough (for sanded grout) or small enough (for non-sanded grout) to be able to support the grout. That simply means that if you are using sanded grout you cannot butt the tiles against each other at the corner and expect to be able to force grout into it. It will not stay if the grout has no grout line to hold onto – if it is simply attempting to grab onto the face of the tiles at a 90 degree angle. There must be a grout line at the changes of plane.
  3. You must decide you are going to use grout at the changes of plane before you install the tile. You can then make sure to leave a line for the grout as well as adding additional support for any spots that may move even the tiniest bit (which it should not do anyway).

If you have taken the above points into consideration and still decide to use grout in the corners – go ahead. The big advantages of using grout here is that it will match all the grout lines and it will never have to be replaced. So although extra care must be taken to properly use grout at your plane changes, the advantages for some people are worth the extra time.

Using Caulk at Changes of Plane

There are several advantages to using caulk in corners and any other area where there may be a plane change or where tile meets another material such as your bathtub or sink.

  1. Unlike grout you are able to use caulk in a corner where tiles are butted against each other. It will stick to the face of the tile rather than needing a space between the tiles to grab.
  2. Caulk is flexible. If there is any movement the caulk is flexible enough to move with it and remain in place. It will not crack out or fall off.
  3. Caulk is waterproof – grout is not. Water will collect in corners such as where your tile meets the tub more than it will on the face of the tile.
  4. If your caulk does crack out or need to be replaced it is easily done.

The only two disadvantages to using caulk instead of grout are that you need to periodically remove and replace the caulk and, depending on your choice of grout, you may not be able to find a caulk that matches exactly. The first reason I consider to simply be regular maintenance and the latter is less of a problem since most major grout manufacturers sell matching caulk.

When to Use Grout

The only time I will use grout for a plane change is when I am using epoxy grout. Epoxy grout is bulletproof! OK, maybe it’s not bulletproof but you can hit it with a hammer a couple of times before it chips. (Don’t do that.) If you are using epoxy go ahead and grout the corners and changes of plane as well. Although it is not flexible it will grab the tile well enough to prevent it from splitting or cracking out. Precautions must still be taken but the Epoxy is strong enough to withstand normal structural movement.

How to Decide

Given the above parameters I believe caulk to always be the best choice. What you must understand about tile installation is no matter where you are installing the tile, it is always a structure that moves, no matter how minutely. Concrete moves, (the ground beneath it) that’s why it has expansion joints – to control where the movement goes. Most shower installations are over a wood structure of some sort. Whether you have drywall, backerboard, or a membrane, if you go far enough behind the tile, you’ll find wood. Wood moves, it’s just a fact of life. Humidity, weather, even the structure’s foundation all affect how much it moves. By taking proper precautions you can minimize the movement, but it’s still gonna move. Taking structural movement into consideration caulk is, for me, the logical choice.

{ 901 comments… add one }

Leave a Comment

Cancel reply

  • russ

    Hello Roger,
    Bet you haven’t heard of this one. I’m tiling a small shower with 12 x 12 porcelain on the walls, attached to waterproofed cement board. I had laid the tile out, both side walls and back wall, using the manufacturer’s specs for the tile’s dimensions (fundamental mistake? not having the tile in hand?), and then tuned my wood framing and cement board installation to come out almost perfectly with full tiles on all the walls; no cuts. When I got the tile home, it measured 11 3/4, not 11 13/16 as stated. All the tiles measured 11 3/4. Being pig-headed and not stopping to think harder ( I know now what I should have done.), I kept setting tiles. And you probably know where that’s left me. I have gaping joints at the corners of the walls! They average 1/4″, pushing it at one place to 3/8″.
    The grout lines in the field tile are 3/16″, per manufacturers spec.

    I hope you can help me. The 1/4″ corner gaps do not look too bad given the 3/16″
    grout line. Caulk? Grout? I had one idea . . . Dural makes a 5/8″ aluminum cove trim to be used with tile (in shower though?, doubt it). I figured that that would hide the gap and go with the schluter jolly trim I used on the leading edges of the side walls. I don’t know how to make it watertight though. Any ideas, or better suggestions?

    Just found your website! In these times, your expertise and modesty are very refreshing. I have complete admiration for tile people who really know their stuff.
    Thanks.
    Best, Russ.

  • Peter

    Dear Tile Elf,

    What is the proper gap to leave in a corner? I’ve read 1/8 for all expansion joints, but my grout lines will be 1/16, so 1/8 will be noticeable. Can I just use 1/16 in the corner or will I regret it? One side of the tile (the hidden side), will of course have the 1/8 gap, if that makes sense.

    This is for a kitchen backsplash.

    Thanks!

    Peter

    • Roger

      Hi Peter,

      1/16″ is just fine.

  • Lisa Baker

    Just removed all the sanded grout from the corner of the floor/wall of a shower because it was cracking and leaking. Now the question…. I bought grout and I bought a sanded caulk…. But the sanded caulk (upon reading the details) says not to use if exposed to water so is there a sanded silicone I should be trying. Seems like regrouting (and option I have) would be silly since it’s already cracked once

    • Roger

      Hi Lisa,

      Any change of plane requires a flexible sealant, not grout (the cracking is the reason). You can use the sanded caulk, but it would need to be replaced every three years or so (regular maintenance, it’s normal). Sanded silicone is not a thing to my knowledge, regular silicone is your best option. It will need to be replaced every 5-7 years, but again, that’s a regular maintenance issue.

  • Krickett Phillips

    We have tiled walls that meet a fiberglass tub. Can I use regular bathroom caulk that is colored to seal that gap (after I remove the old sealant which has area that have come loose from the fiberglass tub)?

    • Roger

      Hi Krickett,

      Yes you can. Unless you use 100% silicone, though, you’ll need to periodically replace it once the bond breaks due to the product shrinking over time (normally 3-5 years).

  • Stephanie Baker

    Apologies for the long query, but I wanted to provide you with as much info as possible. New tile shower installed in June (18×24 porcelain, walls and ceiling, tile sheets over a hand-poured mud pan and liner, which I hope has been properly installed) has developed water seepage from behind the tile at one of the floor corner joints such that the grout remains wet well after the rest of the shower has dried–this has happened three times, most recently last week. The first time my husband (as advised by the contractor, who does not live locally) dug out the wet grout (Mapei, sanded), allowed the space to dry for several days, replaced the grout and let it cure for two days, then applied sealer and allowed it to dry for two more days. It held for a couple of months and then happened again, so installer asked the plumber who installed the fixtures and pipes for the shower system to verify that the water was not coming from the plumbing or fixtures—all looks good. So again, my husband repeated his repair process. The second “repair” lasted about 3 months when last week I noticed that once again the grout was staying wet in that corner as compared to the rest of the shower; the moisture seems to be wicking up about 2-3” from the corner, and also across the bottom towards the right. More concerning is that I observed a small amount of water seeping out from the corner 24 hours after the shower was last used (and after I had dried the floor)—so this indicates that water was definitely getting behind the tile. The good news is by day 3, no more water had seeped out and the grout now seems dry. Installer did not use silicone caulk at the change of planes–apparently grout vs. caulk at the corners is a subject of some debate (yes, I have been doing some internet reading) — but it appears the industry standard, and of course your valued opinion, would have been to use caulk. We suspect that the grout is cracking due to movement (the shower is installed in a bathroom bump out and over a crawl space, and against two exterior walls—though they were reframed and well insulated during the remodel). I can add that in that corner, there is very little gap between the floor and wall tile, and a because a sanded grout was used instead of unsanded, I am not sure if that is contributing to the problem and perhaps the tile can’t hold on to the grout and this is why the grout failed so quickly after the install. The idea of removing the grout at all joints to replace with silicone caulk seems extreme (though I do realize that we should be prepared to experience grout cracking in other parts of the shower over time). Based on what I have been reading, it is not advisable to caulk over grout. I also am not sure even if we remove the grout, how caulking just that corner will look given that the grout and caulk have such different textures, but my husband’s first instinct is to keep it simple and repair the current problem and deal with any future problems as they arise. Another issue is that not only will the installer not respond (and frankly, he has lost our trust), we are finding it difficult to find someone local willing to step in and help. Any thoughts or suggestions you have will be much appreciated!

    • Pam Schnoes

      Stephanie,
      I have no knowledge regarding how your shower base was installed. If you can visit a Home Depot or Lowe’s store ask if they have someone who works in flooring that personally has done tile installing. We were fortunate when we were just learning we had a gentleman who owned his own tile company later selling it to a son. He discussed issues before and during our own install and was happy to take all our questions. As well my husband did a fair amount of YouTube video searches. if you are unfortunate to have a base issue and have to replace it. In our first home I chose a solid onyx base-loved it, fantastically solid. In my second home we bought poly stone. A local company measured the space and mixed their formula for an exact fit shower base, I love these too. My least favorite base are the prefab fiberglass. But one sometimes chooses what the budget allows.
      1) you can not caulk or grout over existing grout. You will need to remove the old grout. There is a tool for this and I believe you can buy them at Home Depot.
      2)There is sanded grout which I used for my flat porcelain surfaces. However if you install glass type tiles one needs a non sanded grout. Think of rubbing sand across glass. It’ll leave scratches. Also there is grout sealer you can add when mixing grout, epoxy for grouting and you can buy premixed grout.
      3)there is sanded caulk and non sanded caulk – you can purchase to match your grout color. I’d use sanded caulk for porcelain and non sanded caulk on glass type tile.
      4)I like using caulk where all 90 degree corners meet another tile wall or ceiling. I don’t care what they say, construction always has wood somewhere that can move. The thought of chiseling out old grout to repair cracked grout does not excite me.
      Finding the problem to fix-i hope you’re guy has returned your call. If not, I would start making alot of calls asking around for a qualified plumber or construction/tile installer for a second opinion. Maybe while they are there you create the problem for them to observe?
      Would the wall that is having a leak be an interior wall? This would give you the option to have either a plumber or a different installer or contractor cut the dry wall on the backside to investigate what the issue might be. Drywall is an easy fix. Altho if it’s at the shower base level that may not be an option. I hope you find a good solution. In no way am I a tile expert, these ideas are only what we researched/found works for how we want to care for our home. I’m a bit meticulous and a perfectionist, not sure that really makes much difference helping solve your issue tho. Good Luck!

    • Roger

      Hi Stephanie,

      First: Water will ALWAYS get behind tile – always. It’s normal. That’s why you waterproof the substrate behind the tile. Normally in a shower will a tiled floor as well, the water will run down the wall over the waterproofing, onto the floor, again-over the waterproofing, then into the weep holes in the drain.
      It sounds to me like that particular corner (and perhaps the entire floor perimeter) has silicone or something trapping the water above the floor. i.e. it runs down the wall as normal, then hits some sort of barrier preventing it from running onto the floor, thus seeping into the grout and out.
      There HAS to be something there preventing that. That would make it incorrectly installed. (the sanded vs. non-sanded actually doesn’t have anything to do with it.)
      If this barrier is around the entire perimeter, it may still just be showing up at that corner, if that corner happens to be the lowest point of the perimeter. The water will run there.
      The easiest solution is to dig out a weep hole in the grout at the bottom of that corner. It’s just an open space where water can run out of the wall onto the floor, then down the drain. Because the water in the wall NEEDS to have a path to the drain.
      The better solution, and the one I recommend, is to remove ALL the grout in every change of plane then silicone them all leaving weep holes.The location of at least one of those should be close to that corner.
      The nuclear option is to remove the bottom row of tile, figure out what the hell is preventing the water from reaching the floor, remove it and rebuild it correctly.

      The fact that water is collecting there isn’t a major issue unless there’s evidence that the water is also getting into the framing behind that area (which would indicate no, or inadequate, waterproofing in that area. Water running out of there is a fair indication that it is at least waterproofed behind that area. It simply isn’t draining the way it should. My guess would be that he installed a bead of silicone at the bottom of the wall for some ridiculous reason.

      • Stephanie

        Hi Roger,

        Thank you for your recent reply. Much has happened since I first posted my query.

        First, thus far we have seen no evidence in the crawl space that water is leaking into the framing. I did speak with the original installer, who strongly asserts that the waterproofing was carefully done, stating that he extended the rubber liner base 8″ up the wall, and applied a liquid waterproofer over the durarock. He did NOT use any silicone caulk. He grouted all changes in plane except for using a matching siliconized sanded acrylic caulk around the shower floor perimeter and in the niches. The instructions for this caulk specifically state it is for use in “predominantly dry areas”– and so I am mystified why it would be considered appropriate for a shower vs. using a matching silicone caulk. However, this installer says he has used this same type of caulk (not silicone) for many years and he has never had an issue.

        In any case, I hired a local tile contractor who stated that his process is to grout the entire shower, and then apply a clear silicone caulk over the grout at all changes in plane (including in the niches)–which has been done. As a side note, I can say that the clear silicone caulk stands out against the matte shower tile, and so the aesthetic is not nearly as nice as the sanded caulk.

        Interestingly, this new guy did not explain that water getting behind the tile is normal–which would have been nice to have understood when speaking with him. However, it is your comments about weep holes that has me concerned because this was not mentioned by the new contractor, and I do not see that any were created–the clear silicone was applied directly over the existing grout. If I am understanding you correctly, by having silicone-caulked over the grout, this could actually make the situation worse by not allowing the water to drain from behind the tile walls, especially given that the entire floor perimeter has now been sealed.

        It sounds like we need to create some weep holes, but not sure if this can be done at this stage. I would appreciate your thoughts given this new information.

        • Roger

          In the case of your shower, with a tiled shower floor, the weep holes I referred you to are not needed when the shower is properly built. In that case the water would run behind the tile down the wall and onto the floor (also under the tile) and into the weep holes in the drain (which are a standard part of the drain). In your case water is unable to run from the wall to the floor – something is stopping it at the bottom of the wall. Grout packed in there will do this (it will slow it tremendously, at least, not necessarily seal it off), but caulk or silicone FILLING those gaps will also do that. It should not go all the way back to the substrate, it should only be as deep as the tile is thick (this is so that water can still run behind it.)

          Siliconing over the grout will only exacerbate the situation as it seals the grout and does not allow it to dry out through the grout lines – it traps more moisture. The weep hole I mentioned will likely solve the issue by allowing water running down the wall to exit onto the floor (above the tile, rather than beneath it). It’s not the technically proper way, but it does get the water to the drain and doesn’t trap it. You can still make weep holes in those changes of plane. Just scrape out whatever combination of grout and silicone they have in there all the way back to behind the tile, ideally all the way to the substrate. The only thing you’re trying to do is give the water a specific place to exit the wall.

          The water WILL get behind the tile. If it does not have a specific method to get into the drain it will build up behind that wall tile (unless the shower is not used often enough, in which case it will dry out through the grout lines, similar to your initial issue) or it will find another route out of the wall.

          The other route out of the wall is normally to keep building and running until it finds a spot which is not waterproofed and exits in that direction – all too often into the wall cavity and framing, or into the flooring substrate rather than a direction into the drain.
          Waterproofing a shower is all about water management. You build and waterproof it in a method that always ends up at the drain in some manner. In a sealed system (tiled floor as well) it is normally behind all the tile, but it still ends up at the drain. In a combination system (tile walls, acrylic or steel base) that is normally behind the wall tile and over the top of the base. Creating weep holes in your existing area creates a combination system even though you have a tiled floor.
          That would be my suggestion at present, see if that solves the issue. If, after a while, you see water running OUT of the weep holes, you have done exactly what needed to be done – give the water a way to reach the drain.

          • Stephanie

            Hi Roger,

            Thanks for the speedy reply to my earlier comments, and for sharing your expertise. I did not understand that water is meant to run behind the tile wall and under the tile floor to the drain, but this makes perfect sense since grout is porous (I did learn that sealing grout is not a waterproofing step). I now do understand that we are speaking about two types of weep holes, those that are part of the drain and those that are required when tile meets a solid surface such as a floor base or a tub, vs. a tile floor. Sadly, in our case, it seems that the water was not properly making its way behind/under the tile to the drain, and thus after time, forcing its way past the grout (or sanded caulk) in that one corner.

            I am grateful also that you have confirmed that the silicone caulking may exacerbate the underlying issue and that we need to ensure that any water that may get trapped behind the tile has a path to the drain, even if has to be above the floor. Can you clarify exactly where we should cut these weep holes (I assume along the floor) and how many? I assume at least one on each wall, or perhaps two along the longer (~5 ft) wall (the opposing side is a knee wall w/a niche, and a glass door).

            Many thanks again!!

            • Roger

              I would put one about an inch from that corner (on either wall) and probably another on the opposite side of the shower by the other corner. That should do it, if it’s not sufficient the shower will let you know by doing the same thing wherever you need another one.

            • Roger

              I would put them about an inch from each corner on the back wall and one on each side wall about an inch from the edge of the shower (inside the glass).

  • Bess

    You mentioned caulking on plane changes and cited wall to floor and wall to tub edge as examples. What about wall to wall (perpendicular to each other)? Some plumbers tell me caulk isn’t needed. Some tell me caulk is needed. I’m confused. Why do they give different answers?

    • Roger

      Hi Bess,

      Any plane that changes direction is a change of plane. If one tiled surface meets another at a different angle, it should be caulked or siliconed.

      As to whether or not it’s needed: Caulk or silicone is not TECHNICALLY needed, as it doesn’t do anything in regards to waterproofing. What it does do is allow two different planes to expand and contract in different directions without compromising the joint. Caulk and silicone allow for this movement – grout does not.
      It also keeps stuff out of that joint – stuff like mold or spaghetti sauce…

  • Tracey

    Hi Roger, I plan on using epoxy grout in my shower and bathroom and I’m hoping to not have to use caulk. We live in CA (earthquakes)… is epoxying change in planes, corners, etc. still ok? Would we risk our tile cracking over time? Our tile are over kerdi membrane, shower pan, ditra (on top or drywall / wonderboard). would we also be able to epoxy grout where tile meets tub?

    • Roger

      Hi Tracey,

      You want to use silicone. You MAY get away with the tile to tub transition, but if there is excess movement and you have an acrylic tub the tub may actually end up cracking before the tile. It is just best to use silicone at all changes of plane for your project. Sorry, I know it sucks. :D

  • Bobby

    I have been trying to decide what do do with the gap between the hardibacker (red guard applied) and the mud shower pan. Second question is the debate on whether to caulk or grout the gap between the wall tile and shower floor tile. I am worried about creating a water damn of some sort. If water were to run down the redgaurd, it would eventually hit caulking and have nowhere to go?

    • Roger

      Hi Bobby,

      Do you have a traditional liner mud bed (the two layers with a liner between)? If so then you don’t need to do anything with it – gravity makes everything work correctly. As far as the ‘dam’, you’re correct, that’s why you need weep holes.

  • Matt

    I have a walk-in shower with marble tile walls and a ceramic tile floor. The grout at the change of plane was cracking, so I decided to remove it and replace with silicone caulk. The problem is that there is grout haze at the bottom edge of the wall tiles from where I tried to patch up the old grout in the past. This haze is proving extremely difficult to remove, especially because it’s on marble and acids are a no-no. My question: Can the caulk (GE Silicone II) be applied over this haze/will it adhere and be an ok seal?

    • Roger

      Hi Matt,

      Yes it will bond, yes it will be okay. The haze is in the pores of the marble (which is why it’s difficult to remove). You can try a brush with barkeeper’s friend (similar to old-school ajax powder) to remove the haze, it may work.

  • Jeff

    Hi Rodger , I’m a newbie that just found the your super helpful Site . I’ve just finished tiling the bathtub walls and two questions if possible . I left 1/8” clean cut space between the tub and walls , can I leave this space open (no caulk) just the outside ends ? And the grout for this subway tile , is spectralock pro your favorite? I I’ve bin all over this website but after finding you I can final stop ……thanks for your time Rodger , Jeff

    • Roger

      Hi Jeff,

      Yes, you can. Silicone is only aesthetic in that particular application. Provided your waterproofing BEHIND the tile is properly tied into the tub so you have a fully waterproof transition from the wall down into the tub you don’t need to have anything there. Keep in mind, however, that it is a perfect spot for mold to grow. You’ll need to keep it clean and dry regularly or you’ll have issues with it. Yes, spectralock pro is my favorite epoxy grout. My favorite regular grout is currently laticrete’s permacolor select.

  • John

    Hi Roger, I’m installing my first tile shower over an acrylic shower pan (Sterling) using 4×12 white tile. I have two questions 1) I had to cut out the durock around the flange clips in order to lay flat just above the flange. Will I be OK if I fill with thinset/mesh tape then run a strip of fabric/aquadefense down to the flange? I am using the Aquadefense to waterproof the entire shower. The tile will drop down to within 1/8 inch of the pan. 2) Regarding the change of plans, can I still leave a gap of 1/8 inch at the corner tiles and fill with 100% white silicone (grout will be white) or do you recommend a butt joint? Under will be thinset/mesh tape (might fabric these also). Thank you. Great website by the way.

    • Roger

      Hi John,

      1. Yes, the mesh tape with AD is fine.
      2. Always leave a joint for silicone.

      • John

        Roger,

        Thanks for the above comment. I’m slowly plugging away on installing the tile and have decided to add a niche. What do you use for the bottom of the niche? Would like some sort of shelf. Saw some large cultured marble floor tiles and thresholds at HD and Lowes that would need to be cut down. Doesn’t have a finished edge though. Have you ever used those? Either that or I can visit some tile/granite stores for a remnant. Also, do you have a grout preference? Was leaning towards the Mapei Flexcolor CQ or Fusion Pro. Trying to stay away from epoxy grout. Tiles are white 4×12 with 1/16″ grout joint. Thank you.

        • Roger

          Hi John,

          I have used nearly everything for shelves. The thresholds work well, you can ‘polish’ the edge of the threshold by coating it with an enhancing sealer, or sanding it (orbital or vibrating sander) with progressive grits up to about 2000 or so, the shine will match the finished surface.
          Both grouts you’ve mentioned work well. I am currently using Laticrete permacolor select as my goto grout – it’s good stuff too.

          • John

            Roger,
            Thanks again for your help. I’ll be grouting this weekend and have a question. Do you grout everything, including the corners, then go back and scrap out the grout in the corners, then apply silicone? How do you keep grout out of the corners without the walls near the corner looking sloppy. Also, how soon after grouting can I silicone? Can I silicone the next day. I’m going with Laticrete 1600 Unsanded with the 1776 Enhancer and using Latisil in the corners/change of plan. Tile is 4×12 with 1/16″ joint. Thanks again.

            • Roger

              Hi John,

              I normally just avoid the corners when grouting and scrape out any grout that does get in there. You can silicone immediately after grouting. The easier, and proper, solution is to silicone first – I just don’t usually do that because of time restraints.

  • Will

    I was planning on grouting the corners, so the tiles are not butted together. Then afterward, caulking over the corner. Is that ok? Or should I just caulk? The gaps are 3/16”. I want to use caulk, but thought you had to grout underneath, oops.

    • Roger

      Hi Will,

      Placing caulk over grout in the corners will just lead to cracked grout in the corners that can not fall out – but it’ll still be cracked. With gaps that large what you can do it install a bead of silicone against one side about 1/8″ thick (leaving the rest of the gap open), then once cured grout between the tile and silicone. This will allow the corner to expand and contract without cracking the grout.

  • Bill

    Our installer did not seal where tub meets tile/grout. So, even though the shower has hardly been used and it has been over a year since last use, we have suddenly developed pink grout! We have tried cleaning with baking soda, hydrogen peroxide, bubbling bathroom cleaner and Clorox and it has not done the trick. Question: can we put silicone caulk over these areas to cover pink without causing further issues? We realize we will probably have to remove, clean & recaulk every year. But is it okay to do this? Any suggestions?

    • Roger

      Hi Bill,

      It is not your grout turning pink. It is likely Serratia marcescens, which is a type of water-borne bacteria. It is commonly referred to as ‘pink mold’. If you google pink mold you’ll find several ways to get rid of it. I would not silicone over it until you get rid of it, that’ll just cause it to flourish.

  • Whitney

    I am using the permacolor grout for my shower. I am going to use either latasil or laticrete premium acrylic caulk for the changes of plane. The laticrete supplier in my area said the caulk is what they sell. I would think the latasil would be the better option but would have to order online. Thoughts on which option is better? Also do I caulk/silicone changes of plane before grouting or vice versa? Finally, I watched the video by laticrete on how to install the latasil and they were using some type of “gasket” in the changes of plane prior to the latasil. They didn’t mention what it was. If that is something I need to use… Then what is it?

    Thank you for all of your help. I bought you liquid waterproofing ebook and it was a great help.

    • Roger

      Hi Whitney,

      Latasil will work better, it’s silicone. Regular acrylic caulk will lose it’s elasticity much faster than silicone will, which means it needs to be replaced sooner. Either works, but silicone works better. What they put in there was backer rod. It’s simply cylindrical foam used to fill empty space before caulking. It’s not a gasket, it’s just so you don’t have to stuff so much caulk in there, it just takes up space.

  • Jaque Christo

    Thank you for the post on using caulk or grout in corners. I like the idea to not have to worry about maintenance with grout until it starts cracking. However, I wonder how much it costs to fix cracked grout as you will need to repair it quickly to avoid water seeping through the cracks.

    • Roger

      Hi Jaque,

      It doesn’t matter if it cracks or not, neither grout nor silicone in the corner has anything to do with your waterproofing or preventing water from getting behind your tile – that WILL happen anyway. That’s why you need to have everything waterproofed correctly before any tile is installed.

  • Wayne Spence

    Yeah… The Elf rules.

  • Ranada Hawkins

    Recently I was fortunate enough to have my dream bathroom become a reality.. We hired a licensed contractor do the work. It’s a bathtub/shower combo with porcelain tiles measuring 3×9 in size. Tiles start at the base of the bathtub & go up to the ceiling. After, cleaning the shower I noticed a Slight discoloration on a few areas on the grout. The discoloration is more noticeable on the very bottom row of tile l, where the tile meets the top of the tub & The bottom corner, but also, appearing along the very bottom row of tile where it meets the tub… The grout is a very light gray & the discoloration appears to be a reddish orange in color.. I just cleaned my shower and I do not have any soaps or shampoos that are that color… I am sick to my stomach about this, as we recently had it done in June of this year.. Do you have any suggestions that I may be able to pass along to the contractor to correct this if an issue?? Thank you, Ranada

    • Ranada Hawkins

      Picture listed

    • Roger

      Hi Ranada,

      First: Don’t panic. :D Everything I’m about to tell you is fixable easily.

      The orange discoloration is mold. It’s actually likely Serratia marcescens, which is a bacteria. It is cause by permanently damp conditions (like a shower), especially at the bottom of the tile wall, which is where the water drains to. It can also be caused by hard water deposits. More likely, however, the biggest issue is that the water behind the tile (completely normal) drains to the bottom of the wall and has no way to escape into the tub.

      Here’s how to fix it: Locations of weep holes in showers