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question LeoT  p_member 
Jul-29-2004 20:53

Dear Tileman: I appreciate your response to my request of 7-16-04. The following is some of the information you requested in regard to the grout problem I have run into: Regarding the question of whether I have two types of tile: I have only one type. What I meant to say in my original request was that when I removed the brown grout with the saw, the tile body that became visible now (with the grout gone) was also colored brown. In retrospect, this was to be expected and did not provide any additional information. I have only some of the information regarding the installation, as a contractor handled the renovation. The tile is Venis Dallas Blanco. The wall studs are regular wood. The contractor said he would use a “dense” wallboard in the tub area. I do not know whether he used noncorrosive screws. Should stainless steel have been used? I also do not know what type of adhesive was used for the tiles and what brand of grout. The grout is white. I do not believe that sealer was used. The only change I made in the cleaning products when I noticed the stain was to increase the use of Tilex for Mildew. From what you wrote, this is bad for grout. I will be receiving information from the local water company on minerals contained in the water. As soon as I obtain it, I will forward a copy to you. Please provide me with a fax number. Leo T.
Dear LEOT:

Hi Leo, well we can give you a bit more information. The manufacturer of the tile "Venis" is one of the leading factories in Spain. The quality of their tile is top class - Congratulations on the choice, I know the tile well. Although the analyse from the water factory may be helpful, I must admit that we are not chemists and your review of the minerals will be likely as insightful as ours. I would look for a high iron content as one culprit. I also believe that there must be something in the construction behind the offending rows of discolored tile that is causing the staining. If we logically describe the situation it goes as follows: In the first several years no staining occurred however after repeated exposure to water and water vapor some metal material (such as uncoated screws or common nails) started to rust behind the mortar or adhesive bed of the tile. Each time the tub walls get wet more of the rusting residue is drawn up through the mortar and finally starts to appear in the grout joint. Removal of the entire grout joint (as you did with a saw) and then application of new grout introduced more water to the suspected area and as the new grout cured, it immediately drew the rusting stain through the new grout. Therefore, the brown staining appeared almost immediately. I truly believe that you have some type of corrosive metal fastener around the location of the staining. If it was a mineral in your water, the staining would be most pronounced in areas of your tile where water concentrates. Your inspection of the tub should answer this for you. Mineral staining should also affect all the tile to some degree and not just in a localized area. Now, I want to cover some other things you've mentioned and then some potential solutions should you need to remove a few rows of tile. Sometimes a type of flashing material is used at the junction of the wallboard and the tub. Because the affected area (last two rows of tile at tub) is in this area, it may be possible that your contractor used something corrosive to bridge the gap and water is wicking up the wall causing the brown staining. Again careful observation of the stains is going to suggest the shape of the culprit. A long running line of stain horizontally may suggest the above. Localized points of stain in a regular pattern approximately the same distance apart would suggest screws or other fasteners. Just for your future reference, wallboard in a wet area should be waterproof. I'm not sure what "dense" means to your contractor but if it is board that is not adversely affected by water than this is correct. Cement board rather than a gypsum based board is the best selection. So Leo that brings us to "should you remove the last row of tile and take a look at what in under there? If nothing else makes sense once you get the water analysis- the answer is yes! You may be able to consider re-tiling only from the affected rows down if you have a good qualified ceramic tile designer in your area. Most Venis tile is sold at factory owned Porcelanosa/Venis retailers. In my experience, they are well trained and should be able to work with your problem. Personally, I would select one of their complimentary bar or wainscot molding pieces that co-ordinate with the Dallas tile. I would re-tile the lower portion in a monochromatic tile of a slightly darker color or I would select the matching Dallas floor tile and run the lower portion on a 45 degree diagonal up to the border tile. I just wanted to give you some additional food for thought, just in case you decide to take down the rows of tile. But we can tackle that once you think you've found the problem. Good luck Leo. Please send any information to the site address listed at the bottom of the contact page. Mark it to the attention of the TILEMAN/ PC, paddy, or DK. You see there are a few of us and will make sure we get the information depending on who is "in town". Hope the suggestions help, paddy
question terryandmarcie  p_member 
Jul-23-2004 16:48

Regarding message 7280. Sorry for the ignorance, but we are homeowners, not contractors. The entire house foundation is concrete. What substrate could have moved? Additionally, as mentioned, the homes in our neighborhood were built by a developer that used untrained workers that were not supervised. If perimeter or expansion joints were not properly included, how can one determine if this is the case for the rest of the tile throughout the house? The developer is financially sound, and will do a complete tile replacement if improperly installed, provided we can show improper installation. We just do not know how to tell if we have an isolated problem or the entire tile installation was improper. How can this be determined without ripping out all the tile?

Good to know the contractor is by your side and wanting and willing to resolve the situation. To begin with concrete moves, cures, expand and contracts throughout its life. It is not uncommon at all for pressure or stresses in the concrete to transfer through the tile. Some common causes of the buckling you are describing are due to exactly what Tileman Numero Uno suggested. Insufficient allowance for expansion and contration joints is the likely culprit. Where should expansion joints be in a quality installation?? First and foremost, there should be a perimeter joint around each room, where floor meets the wall. This 1/4" joint can be left free of any grouting material if you have baseboards or it can be filled with a matching elastomeric caulk if no type of baseboard is installed. This perimeter joint allows for some minimum movement in the concrete slab. Next is to ensure that any interior tiling that continues for more than 24feet in any direction is broken up by an expansion joint filled with an flexible elastomeric caulking. There are other areas which should always have a caulked joint rather than a inflexible cementitious grout. Here they are: At any change in tile direction, such as at a T or L occurring in a corridor: whereever tile abuts to a dissimilar material, such as tile to carpet, tile to hardwood, metal (at a sink) or any protrusion through the floor, i.e plumbing fixtures, columns, pipes; and also over any change in substrate or backing material. This may not be applicable in your case as your entire floor is concrete but it can occur in other home construction. The next most likely cause of tile buckling relates directly to the cement slab: how it was poured; and its condition. When a concrete floor is poured it is sometimes done over a period of time resulting in a first pour and subsequent pours. Where one section of concrete meets the next section poured, this is called a cold joint. Over these "cold" joints in the slab, the installer must place an expansion joint the full width of the concrete cold joint. Regarding the condition of the concrete slab; if the concrete cured with any expansion/contraction cracks in the surface of the concrete, these cracks must be covered with a crack isolation membrane. Membranes can be an isolated "patch" only over the specific area but only if the cracking is very minor. If cracking is more substantial, a full floor crack isolation membrane must be used. If the concrete exhibits structural cracks which are cracks that heave the concrete up and down, these cracks will have a difference in elevation between the two side. This type of cracking cannot be bridged by an anti-fraction membrane. Tiling over a structural crack will almost always result in heaving and cracked tile. Usually ceramic tile covering is not an option over concrete experiencing structural movement. Terry, if you remove several of the tile in the area that is buckling, you may be able to determine if the condition of the concrete is the culprit. Eliminate each possibility I've described and see what is up, or should I say "under" your tile. Check the situation at the perimeter of all rooms and around protrusions. Make sure your contractor has a copy of the Tile Council of America's Handbook for Ceramic Tile Installation. You will find all of the information above on page 44-45 under expansion joints. It gives you complete details on the width of expansion joints and the standard or best industry practices on their installation. Hope this helps. My best, paddy
question terryandmarcie  p_member 
Jul-22-2004 00:58

Dear TileMan: Two and one-half years ago we bought a newly constructed, 3200 square foot home built on a cement slab. More than half of the interior flooring is covered with Daltile Stonehaven, 13-inch x 13-inch, Chestnut ST51. About two weeks ago a bubble, or bulge, formed at the corner of four tiles in the family room. Although our kitchen is adjacent to the family room, we do not believe that any water or moisture from the kitchen made it to the family room. We do not believe that the kitchen has any water-related issues either. The bulge has grown to the point where it is about two inches high, or more, and some of the tiles have cracked in the middle as one inadvertently steps on the elevated tiles. The bulge has taken on a linear pattern, running about twelve feet long and involving one or two tiles on each side along the length of the bulge. The de-lamination appears to be growing. We know that many of the homes in our neighborhood, constructed by a nationwide developer, were built not only with unqualified personnel, but also without any supervision. Could you speculate on the cause of our tile de-lamination? Do you believe that our entire tile installation needs to be replaced to insure that the problem does not show up elsewhere in the house? Even if the cause suggests that the problem is localized, should all tile be replaced due to mismatch of tile lot colors? Thank you in advance for your very thorough and professional advice. Terry and Marcie

I'm sure you would prefer NOT to replace your entire tile floors. The problem you have encountered may easily be isolated to one area. It sounds like substrate movement has caused stresses on your tile installation that likely has been set without perimeter or expansion joints proporly included and obviously necessary. Do you not have some additional tiles onhand from the original dye lot? This is always a recommendation for tile installation. Such tiles will always come in handy and repair the floor, decade later, to like new... whenever wear occurs at entryways or damage from dropping a sledge-hammer...whatever. Mismatch of tile lot colors is one thing... sometimes even finding the tile is another. Ceramic tiles undergo fast aesthetic obsolescence and have a short longevity.... it is a fashion industry. You can salvage some of the tiles that are delaminating and place them strategically, removing and replacing tiles with stone inserts or other decorative elements. (numerous natural stones/ glass/ pewter/ waterjet elements/ mosaics... lots of choices). This will allow you to add contemporary patterning to your floor and fix the problem. Not always is it necessary to replace exisitng tiles with the same tiles of the same dye-lot. Assessment of your overall situation requires firsthand analysis. To be cautious and correct, I would suggest you hire a professional tile-setter to come and review your delamination problems, throughout your home, and make repair and precaution recommendations.
question LeoT  p_member 
Jul-16-2004 16:04

We had our bathroom completely renovated three years ago. This included the wallboards. About six weeks ago I noticed that brown lines had appeared in some of the grout in the first row of wall tiles above the tub. One brown line had appeared in the second row of wall tiles. Some brown lines covered the whole width of the grout; some were narrower. I assumed that the brown color was mold, as we had had mold at times in the past before the renovation. In retrospect, this condition looked quite different from mold, as mold is black and splotchy, whereas this color was uniformly medium brown. I tried to remove the brown with Tilex for Mildew as well as other chlorine bleach products. This would cause some limited temporary improvement that would last for a day or so and then would revert back. As a next step, I removed the brown grout lines with a grout saw and applied new grout. I planned to frequently spray the new grout, as well as the existing grout, with Tilex for Mildew to prevent the recurrence of what appeared to be mold. To my surprise the new grout turned brown within about two hours! Subsequent removal of several of the brown grout lines with the grout saw, application of tile and grout sealer, and reapplication of new grout did not help; the new grout turned brown again within a few hours. This may provide some additional information: upon the removal of the grout with the grout saw I noticed that the color of the adjacent side of the tile was reddish brown. On the other hand, the color of the sides of a spare tile that I have is gray; removal of some material on the side of the tile with a file showed that this is also the internal color. Please provide me with a solution to this problem. Let me know if you need more information. LeoT
Dear LEOT:

I want to begin with telling you to STOP using Tilex or any other type of chlorine cleaner on ANY grout problems. Tilex simply eats at the uppermost surface layer of your joint and effectively removes all the fine sand and colored pigment particulates from your joint. What you are left with is a washed out grout color; a much more porous joint; a greatly weakened joint which is not as dense due to the removal of the fines. Tilex actually perpetuates the need to continue its use because the cement joint, after being cleaned with Tilex, will be far more susceptible to staining and will have microscopic pits in the surface that trap contaminants such as soap film, skin, oil etc. Tilex may be required as a one time last option if and when grout has been left uncleaned and nothing else will restore or remove staining. Even then I would use an industry specific stripper such as products made by Custom Building Products or AquaMix just to name two. These ceramic tile grout cleaners and strippers do not adversely effect the quality of the cement joint. Now onto your mysterious brown stain. I think you are correct in assuming this is not mold. However, something is "bleeding" through the grout joint and based on the color of the staining it sounds more like rust or another contaminant that is reacting with the mortar or from exposure to moisture. In describing the color of the tile body I am curious if you are saying that some of your tile has a brown bisque or body and some has a greyish body. Is this correct? It would be unusual for any tile to use different clays thereby resulting in a variety of different body colors. Please advise what tile you have used. It is very unlikely that the brown staining has anything to do with the color of the tile body simply because clay of any color once it has been fired in the kiln is INERT. Also pigments are not added to the clay mixture (in order to color the tile body) in the production of glazed tile. The color of the body is simply the color of the clay used in production. One way to satisfy yourself that the color of the tile has nothing to do with the staining would be to test the tile (if you have spares)and grout independently of the rest of your installation system. Lay down plastic wrap and place two tile side by side on it. Mix up some grout and put it between the two tile simulating a grout joint. Put another piece of plastic over the top of this assembly and leave it undisturbed for 24hrs or more. Examine this to see if the grout has changed color. Now for some other practical means of determining what is staining your grout. Please tell me what tile you are using; what is the construction layers behind your tile; describe the wall assembly starting with the stud system used; what kind of adhesive (mortar?, mastic?) are you using; what is the brand of grout and the color; what kind of mixing water are you using; what type of sealers are you putting on the grout and the brand? We are looking for a contaminant either behind the tile (something that could rust) or a mineral contaminant in your water that you're adding to the powdered grout, and finally any changes you've made in your typical cleaning products in the last six weeks or since you started to notice the stain. I hope your answers will help us determine why after THREE years without any problems you now have recurring brown lines of stain appearing hours after a fresh installation in your grout. paddy ////////////////////////////////////////// TILEMAN#2 ....I have had similar occurrances. The tile was 8"x10" (20x25cm) from Indonesia and was a white bisque(biscuit) monopososa (single fired wall tile) ... this rust-like colour appeared after a few years and even the tiles crazed in areas that became visible with this discolouration. I thought that it could have been colour bleeding from the installer using interior grade plywood in the substrate. Another time, I found that it was isolated to some areas and that the staining was rust, but in that case it was because the installer hadn't used noncorrosive screws. I believe there is a form of mold that is quite agressive, once it begins. Aluminum Oxide often harbours mold... it is found on the back of tiles. As they come from kilns, this aluminum oxide will not not initially have mold but exposed to high mold condition from deteriorating packaging, high-humity climates, etc. it can be on your tiles, even before they are installed. I have found on some homes that around aluminum window frames this rusty(brown) mould was present but nowhere else in the bathroom. Glazed and unglazed ceramic and cement materials offer nothing for molds to eat and are not hospitable surfaces... this is the reason for using ceramic tile. Mold is not a plant or an animal. It is a type of fungus and a fact of life. According to the Center for Disease Control (CDC), there is always a little mold everywhere and we cannot avoid being exposed to it. It grows year round and is found both inside and outside. Mold has existed for at least 400 million years and doesn't need much to grow. All it takes is moisture, warmth and something to eat. It thrives where there are higher levels of humidity and moisture. Of course, this sounds like everyones bathroom. The National Association of Home Builders says that in just 48 hours, a moist environment combined with the right room-temperature conditions can lead to mold growth. A little bit of mold in your shower is nothing to worry about. While you cannot keep mold spores completely out of your home, regular cleaning can often prevent severe problems before they arise. Log onto the U.S. Environmental Protection Agency's website for more details at
question gregoryose  p_member 
Jul-06-2004 10:36

Hi again Tileman. I need some further advice for my ongoing saga… To be certain, my wife and I purchased and layed out 3 boxes of Daltile’s Terra Antica Oro (sold also as ‘Demetra’ I believe) in an ashlar pattern. It was displayed at a retailer as being a through-body porcelain tile, rated for basically every known tile application there is (pools, walks, exteriors, interiors, etc.). My understanding now is that this is a solid bodied porcelain tile, with a glazed porcelain top. Can you tell me if this is correct? We absolutely love the look for our exterior sidewalk (it's about the only one that makes the ugly brown brick look good), but are now concerned because after we had rain yesterday, we tested the tiles for slickness, and found them to feel more slippery when wet than may be safe. Their COF is 0.60 wet and 0.75 dry. Would you recommend these for an exterior walkway (with freezing temperatures)? If not, can you point us in the direction of finding that look in an unglazed through-body porcelain tile (or anything that would work)? I’ve been searching, but have found nothing that comes close. Thanks again for the site and all your help. Greg

This is what the manufacturer says, "Terra Antica is a glazed porcelain suitable for exterior floors and walls in freezing climates. It does not have any additional " anti- slip" additives on the surface, such as a corundum grit. Standing water will create slippery conditions for any hard surface floor material. Do not use for ramps. Material manufactured in accordance with ANSI A137.1 standards. This line has a strong random shading and placement should be decided prior to installation." C.O.F. Wet 0.60 Dry 0.75; Moisture 0.5% ; Absorption 0.5% ; Breaking Strength 437 lbs; MOH's 8.5; Abrasion Resistance 4 ... I see where you found your Coefficient of Friction, but I have serious concerns if you found it slippery when wet but still it was tested as 0.60 wet. You really should use an unglazed extruded paver for such an application. Looking for acceptable alternatives for exterior pool conditions... ... ... ... ... ...


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