Your letter is informative in explaining the "rules" about tenting and adequate bonds to concrete substrates but lacking in information as to details in the/your installation. Every installation is different, just as we "humans" are different from each other. What will work there might not work here and vica versa. You left out all the pertinent information for me to make a judgment call from a distance. Please elaborate from the "Getgo". Substrate surface, its age, what the condition of it was before tiling? (Previous flooring, if any, and what was done to remove it). What preparation was performed on the slab, if any? What mortars were used; what "specifically" was the tile, including size and description. Was the mortar "keyed into the substrate as required? What size teeth did the trowel have and what was the angle of the trowel to the substrate as the trowel spread the mortar? Was too much mortar spread at one time allowing areas of mortar to "skin over? Were some of the problem tiles wet or dusty when installed? Were tiles occasionally lifted and checked for mortar transference? Were the tiles pressed in and "moved a bit" as required? Were the tiles "beat" with a mallet or beating block, as required? Were grout joints uniform and were tile spacers used? Did anyone walk on the tiles prematurely? Were some of the areas in question in direct sunlight, opposed to other areas? Were there expansion joints in "key areas" and if not, why not? Were there "soft joints" around the perimeter and against solid objects? 1500 sq ft is considerable tile and preventative precautions are always prudent before and during installation. Please answer all these questions, and then I may ask some more depending on your answers. Armen Tavy, "TIRTGIM".

You need the help of the best person I know, when it comes to sealers. Call Dave Glen at 360-733-9029 ext 2145 (Pacific Time Zone) or e-mail him at:  dglen@homaxproducts.com If he can't help you, no one can. If your husband come home before you can find a solution, close the blinds and leave a note saying you had to visit your Mom. If he doesn't look closely he may even think he did it and you may return home and see a note from him saying he had to visit his Mom. Armen Tavy

TAVY Thin-Skin is ideal for your backsplash application. If you hadn't already removed your old counter top, you could have used Thin-Skin directly over the laminate. If your new countertop surface is at least 3/4" plywood, you would be better off using Thin-Skin over the new wood. If you were intending to use cement backerboard over the new plywood, you can save your money for other things. Add plywood strips under the overhang to make the counter edge the ideal 1 1/2" thickness. Go to www.tavytools.com and click your mouse on Ron Hazelton in the left margin for a video over laminate counter tops. Armen Tavy, "TIRTGIM"

If you go to Blanke's Uni Mat web site and read the instructions and disclaimers, it is no wonder that there are so many customer complaints. There are explicit instructions and it is like a jet engine, one part missing and the engine can fail. This is not an isolated case of job failures, they persist in the real world and will continue until every installer "dots all the i s and cross all the t s”. There has to be a common denominator for so many failures and generally speaking, except for a few exceptions, it is usually "OE" operator error. I have never used this product but I have read the instructions, and they are complicated and clear at the same time. Any underlayment product that is permanently fastened to a substrate is susceptible to failures if there are too many "if s" in their instructions. I hope there is someone out there who has a solution for you, but I seriously doubt that will happen. Sorry, Armen Tavy

My guess is that this is another case of grout haze that has cured on the surface of the tiles and then sealed, which compounds the problem. The sealer must be removed and then the "haze" to get back down to the ceramic tile surface, which is a hard glaze that shouldn't be hard to maintain, and is the main reason for its popularity. You must search for a solvent that can get thru the sealer and then look for another one to remove the haze. Start experimenting with a few gel coat type paint removers to remove the sealer if it was a solvent base. If the sealer was water base, the solution will require different chemicals. Aqua Mix, Tile Guard and DuPont all have their own variations of water base sealer removers. Go to their respective web sites and locate a dealer near you and work on "one tile" until you find the "magic pill". From a distance, that's the best solution I can recommend. Armen Tavy

I need your E-mail address so I can send the instruction page. If you want to protect your privacy, send it to spacerman@tavytools.com . Armen Tavy

You were right to be concerened. I will scan and mail you the Tile Council's recomended preparation and tiling reqirements this Saturday. Can't do it any sooner because I'm at a Coverings 2009 Trade Show in Chicago. Work must stop!!!! I also must know if you are in a freeze thaw climate. Armen Tavy

There are several epoxy grout paints that may fill the etched voids in your grout. Check Aqua Mix, Homax and Custom Building Products for these specialty paints in the tile sealer departments of your local tile supply stores. Another option is to remove enough grout, to a minimum depth of 1/8", and then re-grout.  A grout saw, or pointed beer can openers can be used. If these don't work, a "Fein" oscellating grout removal tool will make the job a "breeze". Check your local tool rental locations. Armen Tavy

It's main purpose is to act as a crack suppressant. Armen Tavy

Not having the correct fastener pattern and forgetting the motar underneath the boards are serious omissions. I would loose sleep over this one!!! Armen Tavy

You would have to give us more to go on or give us a better description of the "bullnose tile" and hope one of our readers can help. Armen Tavy

A skim coating with your tile setting mortar and letting it dry to the touch would be sufficent. Armen Tavy

Since he didn't remove the backing, nothing was achieved by removing just the vinyl layer, which if left, would have given you moisture protection between your tile floor and the Partical Board. If he installed the backerboard without a bonding agent, he voided any warrenty you may have had. The backer board manufacturers prefer that mortar be used as the bonding and leveling agent using a 1/4" x 1/4" x 1/4" trowel. Backerboards do not stiffen a floor as well as any kind of 4' x 8" 'wood sheeting will. Particle Boards are sensitive to moisture but kitchens rarely have moisture problems unless a dishwasher or sink related plumbing spring a leak. 1/4" Backer Boards are sufficient for floors and 1/2" is used for walls. Removing the Particle Board and replacing it with 1/2" Backer Board would have not been recognized by "TCNA" as a "legal subfloor" for a tile installation. The Galvanized Roofing nail pattern for backerboards is 8" every where in the "field" and at least every 6" around the perimeter/s and along every seam. #1: Yes, # 2: Not really, #3: A typical warranty can be for life, if all the instructions are followed to a "T". Armen Tavy, "TIRTGIM"

This area is not as sensitive to moisture and if the paint is semi-gloss on the walls and ceiling, Type I Tile Mastic should work fine however, if the ceiling is painted with a "Cheap" flat ceiling paint I would be cautious. If the walls are flat paint, scrub them briskly with a wet face cloth for several minutes, if paint doesn't scrub off onto the cloth it should be fine. If everything checks out, skim coat the walls and ceiling with a very thin coating of the mastic with the flat side of your trowel and let it air dry to the touch plus 30 minutes, before spreading mastic with a minimum 3/16" V-Notch Trowel to set your tiles. Press tiles in and wiggle them slightly before installing TAVY  Spacers with a small dab of mastic on a corner of their disc to keep them from falling off. Remove spacers after tiles have "set fast" (usually within or less than 1 hour) and wash/scrub mastic residue off with a wet rag. If tiles move while scrubbing, re-install the spacers and wait until the tiles don't move. The ceilings usually look better installed on a diagonal. 2" x 6" surface bullnose tiles can be used to terminate the ceiling tiles. When tiling over paint or other questionable surfaces, TAVY Thin-Skin Tile Underlayment can put your mind at ease. www.tavytools.com for sources. Armen Tavy, "TIRTGIM"

Thin-Skin is 30 inches wide and if you center it on the control joint it will give you 15 " of protection on each side of the joint which is more than enough for a 12" or 13" tile, but not enough for a 16". If you plan to install Thin-Skin only on the control joint/s, hold the 5/32 V-Notch Trowel at no less than a 60 degree angle to the floor and spread glue "neatly". Install the "fabric" and use moderate pressure with a flat trowel to imbed the "fabric" onto the 007 Glue so the glue lines are slightly flattend but not "crushed". To give the most positive protection over control joints, allow the installed fabric to "set" for at least 30 minutes before skim coating with mortar. Armen Tavy, "TIRTGIM"

Shot Blasting, sanding, grinding or make your life easy and use Tavy Thin-Skin Tile Underlayment. www.tavytools.com for sources

You should check with the "Kiln" company that you have selected to "fire your tiles" for their recommendations. It would be a shame to ruin the childrens hard work. Glazers are particular about what will work and what won't. I hope you purchased "Raw" un-glazed tile bisque from a tile manufacturer. I would ordinairily check this out further for you but I'm leaving for a weeks stay at our Industry Trade Show in the morning. If you don't get the right answers, please write again. Good Luck, Armen Tavy

Here are a couple of sites you can go to for chemicals.

 http://1877floorguy.amazonwebstore.com/Aqua-Mix-Concentrated-Tile-Cleaner-32oz.

www.homaxproducts.com

Sulfamic Crystals can also be purchased in many tile departments. they can be disolved in water to various concentrations. "TSP", Tri Sodium Phosphate Crystals available in Paint stores is another cleaner. Armen Tavy

Review post number 11988. This is a pro's job or a careful DIY. Use a high end modified (liquid latex modified is best) cement mortar, DO NOT USE Redi Mix TILE MASTICS. If you are nervous, sticks, 1" x 2", can be cut to fit tight under the tiles (slight bow) until the tiles are set, overnight would be prudent. You must use tile spacers because pressure from the "Sticks" could/can cause tiles to drift out of alignment. Please be careful and place soft protection on the floor below the ceiling. If it's over a bathtub, double the protection. Armen Tavy, "TIRTGIM"

If you are looking for a 100% warranty by any mortar manufacturer you must, that's "their" Loop Hole, or you have the option of investing a little extra time and money into a variety of tile underlayments that have their own warranties, including mine. www,tavytools.com  for sources.  Armen Tavy, "TIRTGIM"

Control joints are "saw cut" into a large cement slab by the contractor. If the slab should crack, they would rather it be on a control joint. It may or may not ever crack. It also must be cut deep enough to be effective, so check your local building codes. I have seen some control joints that crack erratically several inches away from the planned control joint in jagged lines. There are products that can minimize or absorb the/a crack so it is less apt to break the tile/s. It is rarely a 100 percent guarantee unless you are willing to spend the extra money and effort required for 100% protection. Uncoupling membranes can work and there are many to choose from. There are high end products like Schluter Ditra; then there are products like Mapei's "MapaLath" as well as others. I have a crack suppressant as well that I call TAVY "008" Easy To Eliminate, which is a "quick release" tiling system that also gives "complete" control joint crack protection and does not raise the height enough to measure. It is also understood that all/any systems will not give protection against "vertical" crack movements. Therefore, the answer is YES, as long as the floor tiles are not "mechanically" attached to the subfloor. One more option, as long as the crack runs straight and "true” on the "Control joint", is to cut the tile at the exact location of the "Control Joint", spreading the two cut sections (grout joint size), then filling the space/cut grout joint, with a soft flexible caulk or use a designed product, i.e. Schluter "Expansion Joint" an other like products. Armen Tavy, "TIRTGM".

The two methods you mention differ depending on whether you are talking about a recessed wood floor or a recessed cement slab. For the latter, it would be difficult to get any concrete contractor to guarantee a smooth, flat recess that would be ready for tile with "Thin-Set" Mortar. "Mud Set" in a deeper depression would be the only way to go to guarantee a flat and level floor, however, I would certainly check the references of the installer to be certain that he was qualified to do a recessed mud set installation, whether it's "Wet Set" or "Dry Set". It's not a job that many are qualified to perform. Wood, unbelievably, would be more difficult to recess (into the floor joists) and still have the room to get the substrate strong enough for tile. The recessed section of the wood subfloor would still need to be 1 1/8" minimum thick and there aren't many builders that are willing to go through the trouble to get it done correctly. If you have one that will, consider yourself lucky. If you go either "recessed way" send me a note with "details" of his plan so I can review them for correct procedures. Armen Tavy, "TIRTGIM"

There are only two main reasons for a "waffle impression" on the mortar after removing a tile. As I said previously, it's either "bad mortar" or "too much mortar was spread at one time". Air can quickly dry the surface of the mortar giving you a false set. If you have any mortar left over from the original installation, run the same test as you did with your re-installed 4 tiles. If they stick and pass the mallet test, the answer is obvious. Give me the name and phone number of the manufacturer you originally complained to and I will personally call them. Include the name of the person you talked with or give me some kind of reference number. Armen Tavy

I don't mind the input but I question the true value of the process. Injecting into drilled voids around a tile/s can only give you a perimeter "tac". The main body of the tiles would still be "un-bonded", "fragile" and probably sound hollow. I can't begin to imagine how long it would take "Catmando" to "doctor up" (not completely repair) a 2,000 sq ft installation. This could be a temporary fix for a small installation or for some one trying to sell a home,..... as long as I'm not the one purchasing it. Thanks for your input Karl, but I personally don't feel that there is any alternative/s for "Catmando". Armen Tavy, Plant City, Florida

Yes, but the same advice still stands. To make it clear, it must be in front of the raised "lip" and not on top of it. There should also be a gap of 1/8" to 1/4" under the backerboard (so it doesn't come in direct contact with the "base itself) which should be filled with thin-set or preferably with an Acrylic Tile Caulk to prevent "Wicking". The first row of ceramic tiles should also be lifted slightly off the base so this open joint can be sealed, preferably with the same Acrylic Caulk. Wash some of the Acrylic Caulk off leaving a small void that can be filled with the same grout as the rest of the installation so everything matches. The reason for this double protection is that shower water can "bounce up" through the smallest crack/joint/space and get behind the tile/s. That is the main reason we don't advise setting the shower walls directly on top of the raised lip that is there to prevent water intrusion to the area behind the "pan" which can eventually cause (hidden from view) mold and mildew. Armen Tavy

This is feeling like a poor choice of a "lower end" modified mortar to install your tiles or possibly an expired (date) product, which are the two main reasons for job failures with Porcelain Tiles. All Post Tension Slabs, as well as regular slabs, are finished with a large rotary magnesium float which produces a slick finish. We (The Industry) "hate" slick finishes on concrete and these surfaces should be "scarified" before tiling, however, you are not advised to "Scarify" Post Tension Slabs. If you had used a "Liquid" Latex Modified Mortar, instead of just an ordinary Polymer Modified Mortar, to properly skimcoat your slab and allowing that skim coat to dry first, and then set your tiles with the same mortar, you would probably not have lost your floor. If you had used my TAVY Thin-Skin Tile Underlayment before tiling, your mortar (any kind) would not have come off the slab like "pancakes". Buttering the floor is not the same as "Keying it In". To correctly "Key In" you must use only a small amount first and "scrape it in" with as much force as possible leaving only a thin film of mortar behind. Excessive thickness/buttering without pressure is not the correct procedure. It's like putting a wet pancake mix on a skillet that has been sprayed with "Pam". Sorry, but the odds are that your floor is a total loss unless you have the patience and fortitude to clean all the mortar off all the tiles so you can re-use them. What expert did you consult before you started this expensive project? Armen Tavy, "TIRTGIM"

PLEASE read my reply to 11989!!!! Armen Tavy

If I'm understanding you correctly, you are concerned about a space below the backerboard that is recessed and you would like to build it out. You previous installation should not have been flush with the base walls and neither should the new backerboard. It should not be resting on top of the new shower base walls, even if it's only on it partially. Any moisture or condensation on the "backs" of the boards are supposed to "dribble" down into the the shower pan and not be deflected by the walls which would allow condensation to leak behind the pan. Your backerboards should have been shimmed out so that the boards drop down in front of the pans walls with a small air gap behind them. THEY SHOULD NOT SIT ON TOP OF THE BASE/PAN'S WALLS/SIDES. The backerboards should not go closer than several inches to the proposed height of the new ceramic tile surface, to prevent "Wicking" of water up into the boards. The space below the boards (the walls of the base pan) should be coated with thin-set with a throw away paint brush and then filled/packed flush to the face of the boards with the same "Dry Pack" you will be using to fill the shower pan. This seperate "fill" will break the siphone (wicking) effect. If you don't understand this, write again. Do not fill the space with 1/4" or any scraps of backerboard!!!! Remember to keep all "weep holes" in the sub-drain open and un-restricted by using a cup full of small gravel or tile chips around the sub-drain before filling the pan with "Dry Pack".  Armen Tavy, "TIRTGIM""

It's a good practice to always use at least a "Modified" Thin-Set Mortar. That is any dry set thin-set that has powder polymers added to the dry mixture. The polymers enhance the bond and also give mortar flexibility. Many companies usually have more than one grade priced accordingly. "Porcelain" tiles are extremely dense and are best set with mortars that require their own Liquid Latex Additive. I certainly would not want a ceiling tile falling on my head. It is your choice, Good, Better, Best. If it was my ceiling, I would skim a very thin coating of thin-set on each tile just before installing. The correct trowel to spread the mortar is also important. Nice neat "Corn Rows" of mortar spread with a 1/4" x 3/8" x 1/4" trowel would be my choice. Press tiles in place, "wiggle" a little and install spacers to keep tiles in alignment. Tavy "Tile Spacers" have a disc in their center that can be spotted with a dab of mortar to keep them from falling down. Remove the spacers after the tiles have set and sponge wash the residue. Don't wait longer than a couple of hours to wash mortar residue. "Note: Be neat, because to much mortar is not necessarily better. Too much will allow the tiles to "slip" from their own weight and possibly fall to the floor before they set. Keep an “eye on" your ceiling installation for the first 1/2 hour after completion. Armen Tavy, "TIRTGIM"