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Tom Magg 

Nov-30-2004 20:25

Hi Tileman, I have an another question. I plan to continue the tile from my den to a new room. There is a threshold of about 3" with a header joist, some flashing, and a gap, all of which is about 1/2" below the plywood surface of where I plan to ceramic tile across. I could easily fill this with a self leveler to make this level across the den and the new room. However, I am concerned about deflection between the floors of the two rooms. One thought I had was to cut up a 4'x4' section of plywood on both sides and replace with a 4'x8' sheet of plywood going across the transistion. Would this help/be better than the leveling cement and allow the tile to go across the joint? Any other suggestions? I read many of your other responses and it sounds like a work around would be to make sure there is a grout line over the transition between the two rooms and use something flexible for the grout joint. If I took this approach, then does it matter if I use a leveling patch or use the effort of having a plywood surface across the two rooms? Thanks, Tom

Dear TOM MAGG:

ic Man! You are thinking... it would be better than leveling compound, but more work. Several options are possible. The ones you have mentioned do work. You could primer the wood and fill the area with self-leveling comound, then apply a sheet membrane to bridge across the area.

Tom Magg 

Nov-30-2004 19:16

Dear Tileman, I tiled my entrance foyer (approx. 12x14) last year putting 16"x16" tiles over thinset over 1/4" backerboard screwed down over existing vinyl which was glued to thin plywood (luan?) which was glued to 3/4" plywood on wood joists. I am now planning to tile the adjacent den (22x14) which is 3/4" plywood over wood joists. To match the height of the foyer (which is 1/4" higher to start with than the den because of the lino and luan), I have two options that I can think of: (1) use 1/2" backerboard or (2) put down 1/4" plywood and then 1/4" backerboard on top. Which would provide the best structural support? Or is there a third option that I missed that would be better? Thanks in advance, Tom

Dear TOM MAGG:

I got it...I got it... MAGGIC #7777 "There are seven sins in the world: wealth without work, pleasure without conscience, knowledge without character, commerce without morality, science without humanity, worship without sacrifice and politics without principle." (Mohandas Gandhi) .... What about "industry without direction" ???? Tom, you have a handle on it and some experience. You're just looking for a second re-affirming opinion. Your simplest and best solution is the 1/2" cement backer unit, as you suggested. This would provide correct and acceptable deflection support. Always follow manufacturer recommendations.

brian 

Nov-30-2004 15:29

i have layed thinset over 3/4" subfloor and installed 1/2 hardibacker cement board for floor tiles in a 40 square foot bathroom area. I've now discovered that my floor is flat but not level. It's 3/8" out across a 5 foot span. Should i pull it up and level with leveling mix or will I be okay tiling on a flat but unlevel surface? If I do have to pull it up, what will I do to get the dried thinset up off of the subfloor?

Dear BRIAN:

With that small variance, over that square footage, within a bthroom, you are fine to proceed with tiling....NO PROBLEM!

debfisher_4 

Nov-30-2004 13:05

I just bought a 2 piece shower enclosure and ordered a dome later. I just started to get back to the bathroom to finish it but I don't like the looks of the dome and the shower is already installed. The shower walls are only 70 inches high. Is this high enough or will the drywall above get water damaged over time? Or should I tile above? If so, how high? Thanks!

Dear DEBFISHER_4:

You should really tile above the 70 inches... right to the ceiling.

David K 

Nov-30-2004 12:47

Hello Tile Man: My question has been partially answered by 7738. I will remove all wallpaper. My kitchen counter backsplash will be 1 level (6 inch tile) high. Would it add integrity and strength by covering backsplash base with fiber mesh tape and then covering with thin layer of non-sag thin-set? Thanks for this forum,

Dear DAVID K:

No need for the fiber-mesh tape.

Steve 2004 

Nov-30-2004 08:54

I can't belive you deleted me, I followed all of the rules, I checked the archives (as you instructed) and cannot find an answer to my question about cool decking...and yet you still deleted my question about tiling over cool decking...So, I will assume that your fingers are swolen from all of those years of tiling and my message was deleted by accident...now 'cmon, my customer and my bank account need to know! Thanks

Dear STEVE 2004:

Unfortunately, there are three of us that answer these questions and you did not post you question during my 2 days Monday and Tuesday. Post it to my attention all the details and I will answer DK.

salvequin 

Nov-30-2004 08:52

I had a professional install my mud shower pan and he had to come back and do some patch work because it was crumbly and soft near the drain. Now I am tiling and screwed the drain part down to check the height, but I have turned it as far as I can and it still is about 1/8" above my tile level. These have to be perfectly flush, right? And if so, I'm assuming I need to sand the patch work around the drain down a bit, but how is the best way to do this? Thanks!

Dear SALVEQUIN:

Yes the drain grate should beflush or even slightly lower than the tile surface. To get the patch lowered I would use a grinding stone or use an 4 1/2" grinder with a masonry blade. Your welcome, DK.

Dave 

Nov-30-2004 00:43

Hi Tileman, I am writing about question number 7711 from Armando Sillas. He asked about a good set of knee pads. What do you think of the knee pads they sell at www.proknee.com ? Have you ever tried them, and if so, are they worth the investment? I haven't found a perfect set of knee pads yet, and my knees are killing me from doing installations for 14 years. Thanks for your time.

Dear DAVE:

Yes, they are well worth the investment. I have a pair myself and I can be on my knees all day long and then go out and rollerblade or play hockey with absolutely no pain or fatigue in my knees. Thumbs up, Dk.

Marisa 

Nov-29-2004 23:57

Hi Tileman, You're an excellent resource, I am installing 13x13 ceramic tiles in a home entryway. The thickness of the tile is about .5". I am trying to match the tile height to an existing wood stair nosing that is at the top of a stairway coming up to the entryway from the level below. Currently there is marble tile laid in the entryway which exactly matches the height of the stairnosing. I plan to lay the ceramic tile on top of the marble tile. Obviousily, this will make the height of the cermaic tile higher than the stair nosing. One option was to place a bullnose at the edge of the ceramic tile and have a transition to the stair nose, leaving the stair nose's wood exposed. But the transition is a few inches from the edge of the stair (possibly a trip hazard?). Another option was to extend the tile over the top of the stair nose. It is difficult to remove the existing stairnose without damaging it. Do you have any suggestions on how to handle this? here are a few pictures to describe my situation about how to lay the tile at the top of the stairs. http://www.fototime.com/inv/70BC73D0B5313CB. Thanks much! Marisa

Dear MARISA:

Thanks for the Photos, it is a nice way to show your dilemma. I have a couple of Schluter solutions for your. One I would cut the radius off the edge of the stairnosing and then apply The Schluter Rondec Step see http://www.schluter.com/english/products/2002/sectionb/rondecstep/208-index.html. Another possibily would be cut the radius off the stairnosing again and then Use Schluter Trep Stair-nosing and the use a Schiene profile upside down to cover up the exposed wood see http://www.schluter.com/english/products/2002/sectionc/treps/302-index.html. Any questions let me know, Dk.

John 

Nov-29-2004 16:15

Dear tileman I am installing ceramic tile on the floor over a crawl space. I plan on using 1/2" sub floor and 1/2" cement board. The floor is insulated but feels pretty cold in the winter. do you approve? Thank you.

Dear JOHN:

Do you mean that you have an existing 1/2" subfloor which then you will apply the 1/2" C.B.U or do you mean to add on top of the existing sub-floor (5/8") and then add the 1/2" plywood and C.B.U.. If it is the prior versus the latter then you will be fine. If it is the latter than you are pushing the threshold, no pun intended. DK.

 

Nov-29-2004 14:48

Dear tile man I am adding a playroom and a bathroom in my 3rd floor. I want to install ceramic tile in the bathroom. Do you think that the floor is going to be good enought to hold the ceramic tile. Do you think that the tile will brake or chip. If so, what can i do to help it braking and chipping.

Dear :

Look in the archives under; 16" o.c., single layer plywood, double layer plywood, or other combinations. DK.

Josh 

Nov-29-2004 14:25

Dear Tileman, This may seem like a silly question, but my wife and I just bought an old house, with a ceramic tile bathroom in it. Unfortunately, the tile style is quite dated (and ugly), and we won't have the money to replace with new tile for a few years. In the mean time, I'd like to put up some plain white beadboard directly over the tile on the walls--until we get the money to redo the bathroom. Is there anyway to predrill/screw, nail, or otherwise attach the beadboard directly on the surface of the tile? (the tile is 4x4, and on the vertical wall)? Thanks for your time! -Josh-

Dear JOSH:

There a special bits that you can use to drill hole into most wall tile, but if it is porcelain you will have to spend a lot of money to get a bit that can cut through such a hard surface. Another, possibilty would be to use an adhesive to ashere the board to the existing tile. Dk.

 

Nov-29-2004 14:14

My backerboard is slightly uneven at the joints. I have used about as many screws as I could to try and level it out but my tiles still rock a bit at the seams. I am worried about laying my tile down in this condition because I feel they may break when stepped on. Any suggestions on how to "level" the floor or prepare the tile to prevent any damage to the final project?

Dear :

The recommendation is to use fasteners every 6" around the perimeter and 8" throughout the body. Did you put a leveling coat of mortar underneath the backerboard as well. In addition, you may want to use some of the alkali resistant mesh over all the joints to help give a little more stability to the substrate. Also, did you make sure that you staggered your C.B.U. sheets so the joints did not coincide with the subfloor. Also, for best results the joints should be staggered so they are 1/4 the distance from the joists i.e. 16" o.c. it would be 4" away from the joists. Hope that helps, DK.

Mr. Selby 

Nov-29-2004 09:01

I have just purchased and laid Italian Quartzite floor tiles, which are dark grey (with a slight sparkle to them). I have laid them and grouted them and they look terrible becauase it seems to be very difficult to clean off the dust of either the adhesive or grout. The shop is adamant that they do not need any additional sealant. However, the only time they look nice is when they are wet. When they dry, they just look dirty as if they are embedded with chalk dust. Would adding a gloss sealant make them look better do you think? There seem to be some similarities with slate flooring here which looks dusty when it is taken out of the box, but then looks very different when brushed with a sealant glaze. Any advice would be much appreciated.

Dear MR. SELBY:

First, try to clean off any grout or adhesive residue with the same named cleaner from any of the cleaner/sealer companies such as Aqua-mix or Tilelab from Custom, or Lithoflin, or Miracle Sealant. Once that has been done, if you still want to have a wet look, try some of the different sealers available from these same companies and see which ione gives you the look you want. Dk.

Denny 

Nov-29-2004 08:04

I am a contractor and I spilled an acidic product on ceramic. It dried leaving a milky splotchy residue My question is what is the strongest chemical I can use to remove this residue? And if the surface is damaged can I use honing powder along with a scrubber to bring back the finish to its original shine. thank you

Dear DENNY:

I would try using a poultice and/or a sulfamic acid. If this does not work graduate to a phosphoric acid. If you know what the product is that you dropped I would call a couple of the Cleaner and Sealer companies like Aqua-mix and see if they would have a specific recommendation 800-366-6877. Your welcome, DK.

jacki 

Nov-29-2004 02:39

My saltilo tile is having grout prob's. The grout is chunking out. We just resealed it in July so the sealer should be holding. There are some pinholes that have appeared out of the blue & there are pieces of grout that just fell out....nothing was dropped or moved...unk why. What do we do to fix it. The tile cost alot & the tilesetter isn't ret'g our calls. What do we fill it in with & how? thanks.

Dear JACKI:

the good news is if it is only the grout that is failing this can be replaced relatively easily. Use a tool like the grout grabber (see archives)and then regrout.DK.

kendell 

Nov-28-2004 22:20

Can I use a foil vapor barrier instead of plastic behind my green board before putting tile around tub?

Dear KENDELL:

Yes, you can....foil barrier film is at the top of the chart with the lowest water transmission rates. HERE'S A GOOD ARTICLE... Understanding Vapor Barriers By Paul Bianchina ... One term you'll often hear thrown around, especially when talking about insulation, is "vapor barrier." It's important to understand what a vapor barrier is, and what it does to protect the warmth and integrity of your home. Through a process called convection, warm air will always move toward colder air, meaning that during the winter the air inside your home is always trying to escape the house and move toward the cold air outside. Warm air also expands, and therefore has the capacity to hold more moisture than cold air -- moisture that is picked up naturally from inside your house. As the air cools, it contracts and loses some of its capacity, so the moisture is given off to cooler surrounding surfaces. The result of all this is that warm, moisture-laden air is constantly on the move from inside to outside. As it leaves the warm interior of the house and enters the walls, attic, and crawl space, it cools off and gives up its moisture, which in turn can saturate the insulation and framing. The more moisture there is in the air and the more differential there is between the inside and outside temperatures, the worse the problem can become -- in the more extreme cases, the insulation is rendered virtually useless and severe rot can take place in structural members. It is the purpose of the vapor barrier to prevent that movement or penetration of moisture from one area to another. Placed between the inside of the house and the insulation, the vapor barrier acts as a physical shield to repel the moisture and keep it from entering enclosed cavities where it can do serious damage. Vapor barriers can be created from a variety of materials. The only requirement is that the material be resistant to moisture, which is indicated by its vapor permeance value, called a "perm" rating. To be an effective vapor barrier, a material needs to have a perm rating of 1.0 or lower. Common vapor barriers used with insulation include plastic sheeting, foil sheeting, and kraft paper that has been treated to achieve the proper perm rating. Vapor Barriers in the Home One of the most important vapor barriers in the home is the one between the wall insulation and the interior side of exterior walls. Because wall cavities are sealed and have no means of allowing accumulated moisture to escape, an effective moisture barrier is crucial in preventing warm, wet air from entering the walls. For wall insulation, foil- or kraft paper-faced insulation is typically used. The insulation is installed between the studs with the vapor barrier facing in toward the house -- the one thing to remember about vapor barriers is that they are always installed between the insulation and heated portion of the house. The "wings" along the edges of the insulation are stapled to the studs to hold the insulation in place -- stapling to the face of the studs instead of the sides creates a more effective vapor barrier. Another alternative for walls -- which is also commonly used in the enclosed cavities of vaulted ceilings where the pressure of warm air trying to escape is even greater -- is to place unfaced insulation into the cavities between framing members and then cover the insulation on the inside with plastic sheeting. The sheeting is stapled to the face of the studs or joists, and overlapped at all seams to prevent moisture penetration. In today's construction, separate vapor barriers are typically not used between the home's interior and a ventilated attic. Most attics are insulated with blown fiberglass, which is relatively porous in comparison to the denser batt insulation used in the walls. The attic also has a continuous flow of air through it that is created by the roof and soffit vents, so moisture from inside the house passes through the insulation and is removed from the attic by the air currents. In areas of high humidity where moisture in the attic could still be a problem, a vapor barrier paint can be applied over the inside ceilings. Another area that typically does not have a vapor barrier is the floor. Most of today's homes are now constructed with subfloors of interlocking tongue-and-groove plywood or other sheet materials -- waterproof resins are used in the making of the sheets, so the subfloor itself becomes an effective vapor barrier that protects the insulation below it. A vapor barrier is used, however over the ground under the house. Typically a layer of 6-mil plastic (1 mil = 1/1000 of an inch) that is laid directly on the dirt floor of the crawl space, the moisture barrier prevents ground moisture from entering the enclosed crawl space and wetting the insulation or the framing.

Barbara   

Nov-28-2004 21:43

Dear BARBARA: Because they are interior wall, you are likely fine. It is done... take a wait and see approach. Your contractor is like the pilot of a plane. He is able to assess, better than anyone not there inspecting or working to understand the specifics of your installation, and conclude acceptable results and practices. He is not attempting to crash your project... it would just hurt him. I will not recommend that you take any action. MR TILEMAN: Thanks for the quick reply. I have been trying to find someone to give me hope, because I don't know what can slide and what can't; how moisture makes its way back that far from the CBU to the studs. Thanks for your input, which I surely trust and will hope for. Believe me, though, even I know these guys are not pilots bringing in this plane. I have skills and know what it means to be good at something. And, they are trying to cut any corner they can get away with. So many thoughtless, stupid things have been done in here, even tiling over open seams. How can one keep the faith? But taking the whole thing down is very unappealing and will cause some very big financial issues to deal with. I just won't be able to fix my only bathroom in 10-20-30 years. This was a once in a lifetime project. They do have repairs ahead though, and tiles are going to have to be pulled to check the other seams. Some are packed but not taped, for instance. There is uneven (dark) thinset application, causing both oozing and voids underneath (one tile corner has already broken off). Expansion joints weren't allowed for, have some hairline tile cracks already. Chipped tiles were installed. Very embedded spacers. You name it, it's probably been done in here. Sigh. Thanks for your help.

Dear BARBARA:

SEE #7750

Tony 

Nov-28-2004 20:59

Great Forum here. Question. I've been all over the city trying to find a mortar for the floor of my shower. It seems like all the mortars say "not to be used in heavy water areas. I have UltraFlex 2 for the walls and Ultracontact for the floor, will this work???

Dear TONY:

Yes... you can use UltraFlex 2 for both your wall and floor of the shower.

clueless 

Nov-28-2004 20:44

ripped down my tile and walls in my shower, and know theres a gap about inch an a half wide an about 2-3 inches deep between the subfloor and the walls. Will this gap be filled with durarock and tile, or should it be? If not do I just level it with the floor, and then install durarock and tile? Please help!

Dear CLUELESS:

Yes, you should use a primer then fill this using self-leveling compound. Even the Durock will not come down and touch the new surface... it should stop short 1/4" and be filled with a DAP white 100% silicone sealant.

Siberian64   

Nov-28-2004 19:52

Hi Tileman! I am laying saltillo tile for the first time. I mixed up a batch of thinset; Custom Building Products brand Standard Masterblend Mortar and the Acrylic Admix. The recipe is 1 gal of admix to 25 lbs of mortar. I screwed up and assumed that the "handy pre-measured" container was 1 gal and used the whole thing in 25 lbs of mortar. The container is actually 5 quarts (go figure). I thought it was a bit runny, but the 1/2" trowel ridges held up a bit so I proceeded. I layed 40 sqft in the laundry room so if it fails it's not a disaster. Will it simply take longer to set and cure or is the proportion such that it will never cure?

Dear SIBERIAN64:

Definitely the excess will take longer to dry or cure. I don't believe it will not set. It may cause you troubles during grouting with some potential latex leaching... whiteness drawn through the grout from the mortar, unless you give it more time now, before grouting...normally 24 hours, under normal drying conditions... I would give 48 hours. It was a good sign that the 1/2" trowel ridges held up.

 

Nov-28-2004 14:29

Can I repair cracked or broken tile without replacing it

Dear :

No. Not really... this is why we suggest that for all tile jobs, the owners keep a few boxes onhand for future repairs, from the same production and dye lot.

Barbara   

Nov-28-2004 13:58

I'm very concerned that my professional, NTCA tilesetter did not install a vapor barrier behind the PermaBase CBU (over wood studs and firring strips) in my tub/shower alcove. They are interior walls. What do you think about this practice? Do you always do this, and do you think it will probably be OK? I don't know what to do about the situation since most of the tile is up (not yet grouted). Thanks.

Dear BARBARA:

Because they are interior wall, you are likely fine. It is done... take a wait and see approach. Your contractor is like the pilot of a plane. He is able to assess, better than anyone not there inspecting or working to understand the specifics of your installation, and conclude acceptable results and practices. He is not attempting to crash your project... it would just hurt him. I will not recommend that you take any action.

Phil 

Nov-28-2004 12:45

I have bought this Italian ceramics to be used in our kitchen as splash guard ajacent to the stove. Our existing dry wall has a textured wall paper. Do you have any step by step procedure on how I would tackle this? Thanks.

Dear PHIL:

Remove wallpaper, sand surface flat, use non-sag thin-set mortar and recommended trowel, float sanded grout....follow all manufacturers instructions.

Barbara   

Nov-28-2004 03:28

Hi Mr. Tileman, I'm very concerned that my professional, NTCA tilesetter did not install a vapor barrier behind the PermaBase CBU (over wood studs and firring strips) in my tub/shower alcove. They are interior walls. Do you always do this, and do you think it will be OK? What do you think about this practice? I am wondering why water would be absorbed through tile and sealed grout, why it would ever get through the CBU to the substrate, hence the need for a vapor barrier. Isn't tile and sealed grout/caulking providing a waterproof surface?? Thanks much.

Dear BARBARA:

Sealed grout does NOT provide waterproofing... I agree, if it did, there would then be no need for membranes or vapour barriers.

salvequin 

Nov-27-2004 19:55

I recently began laying stone tiles that were slightly irregular on a mud shower floor pan. I drew my lines for the four quadrants like I have always done before, but didn't realize until I was already into it that with tiles that are not exactly the same it is very easy to get out of square. Now I am unhappy with what I have done so far because by the drain I have between a 1/4 and 1/8" space and back by the corner I had to butt them up against each other just to fit them in. My question is this--can I (somehow carefully) get these tiles out and start over without having to replace the mud shower pan I just had installed for $450?? If so, how, and if not, what are my options? Thanks in advance!

Dear SALVEQUIN:

The sooner you begin, the better. It will continue to bond and harden. You need to remove the tiles with a chisel and hammer... of course, working horizontally as much as possible and prying up the tiles. Once finished, some of you shower pan surface only may come away but you can patch this with cementitious patching compound, not gypsum based.

 

Nov-27-2004 16:16

What is a linear ft.?, and how does it compare to a square ft?

Dear :

Linear... long, uniformly narrow, straight line... it is simply a one direction line... like a ruler or measuring tape... 12 inches (12") straight long line(304.8cm) is one linear foot. Of course a square foot is area, 12"x12" (304.8x304.8cm) 144 Square Inches or (929sq cm / Square Centimetres) It is like a square sheet with 12 inch sides 4 joined linear 12" lines making a perfect square)

Cathy W 

Nov-27-2004 13:05

Hi~ I am refinishing an old record cabinet to be used as a liquor cabinet. I have it sanded and painted and now I would like to tile the top of it. This would help to prohibit issues with water, spills, etc. The problem is, how do I go about tiling over wood and paint? Sounds like a very silly question, I know. However I do not have a clue as to how to go about this other than measuring and coming up with the number of tiles I need to complete this project. What kind of glue, epoxy, mortor, etc should I use? Is there a special type of grout that I have to use? Your help and expertise is greatly appreciated!!! Thanks so very much! Cathy W in Gettysburg

Dear CATHY W:

Well, first you at least recognize you're doing something contrary to recognized and recommended use... but I have and many people have done it successfully. It's mostly how you handle them afterwards, accepting that they are don't designed for leaning,moving agressively, etc. You need to unpaint it... the best would be bare wood. The recommended mortar and/or grout would be 100% solids / modified epoxy designed for setting and grouting ceramic tile. it is available at ceramic tile specialty stores and large building suppliers.

Tony 

Nov-27-2004 11:50

Hello Tileman. I am installing 2 ceramic, stone medallions in the center of an oak hardwood floor (one in the entrance one in the kitchen) and would like info on grouting details between dissimilar materials. After taping off the hardwood floor should I just grout the whole medallion including the 1/8 inch spacing between the medallion and the hardwood floor, or should I grout the whole medallion except this 1/8 inch space and caulk it instead? I also read about Grout with plasticizers will this be the solution for a floor that might still have a little flex even after intalling a ceramic backer. Thanks in advance

Dear TONY:

You need to have the separation. The joint should not be filled with rigid grout. Have you considered decorative expansion or control joints? GO HERE AND HERE

Julie Tadros 

Nov-27-2004 11:07

Please Please Please help me! I am writing a school essay about the differnt types of flooring for an outdoor garden patio, part of my essay is to evaluate their physical properties. the floorings I am writing about are: Bricks Concrete tiles Clay (Terracotta) Limestone blocks Clay (Porcelain) Terrazzo Clay (Ceramic) and the physical properties I am including in the report are: Water Absorbency Minimum % Abrasion Resistance Compressive Strength N/mm² I have two values missing: Compressive Strength of Porcelein(fully vitrified) Compressive Strength of Ceremic(vitrified) Please help me find these values in N/mm² because I can't find them anywhere. Also, do you think the properties I chose are enough to evaluate the physical quality of the tiles? In your opinion do I need other properties such as: Flexure Resistance Modulus of Rupture N/mm² (because I can't find those either). Please help me if you can. Thank you very much for you help.

Dear JULIE TADROS:

Yes, #1 is water absorption ...the lower the better. It is an primary indicator of all other physical property values. Lower the water absorption and you improve stain resistance, breaking strength, durability, etc. The compressive strength for ceramic and porcelain is NOT a common need or recognized industry standard ISO testing requirement....just the 'modulus of rupture or breaking strength. You must understand, these are tiles, not structural elements. You will not find 'Compressive Strength' as you would with limestone or bricks. You can be sure that because of their nature and density that they will most often exceed that of limestone, bricks or even the concrete to which they are applied.