Ceramic/Porcelin tile floor help?

Question

I am going to put ceramic tile, (most likely unless a good deal pops up on porcelin), on a concrete floor. I have scraped all of the old vinyl floor off of the concrete and have gotten almost all of the glue up with the exception of little spots here and there. A neighbor came over and told me that I need to clean the concrete real good before I start applying the tile floor. Is this true and if it is what is a good product to use?

Answer 1

What he probably meant was get all the loose dirt off the floor. If you have spots hear and there, try to take them off, or at least make sure that it won't come loose with moisture. Since thinset is mixed with water, it may come loose on you. It would be a shame since concrete is the strongest substrate for tile floors.
If they are just little spots and most likely will not come up or interfere with the height of the trowel you are using (e.g. 1/4"x1/4"x1/4" trowel), you should be fine. As far as the other complaints here, they are talking about installation on subfloor without proper prep (i.e. cement board) and/or coverage on the back of the tile. Email me if you have any questions.

Answer 2

Installing tile over concrete is the best way to install floor just make sure all the cracks are filled in with a ardex filler or even mortar smoothed out. As far as the old tile glue on just try to scrap it clean as best as possible and go from there. Also make sure u sweep and clean the area good free of dirt as best as possible.

Answer 3

You do not need to clean with an acid.

There are several types of mortar base you can use for different kinds of floors that you are going to bond a ceramic or porcelean tile onto. If you go to Lowes, the salesperson can explain that to you. The cost varies accordingly, for Porcelean to concrete its about $40 a bag and it has the latex bonder in it. The mortar base for regular ceramic tile is about $18 to $25 a bag.

On tile cracks, the reason that happens is inadequate application of the bonding mortar. On porcelean tile, about the best technique is to trowel the floor with a grooved trowel in one direction, then also trowel the backside of the tile and apply that tile groves to the floor mortar at a 90 degree angle to the grooves in the floor grout. In other words, cross them. With this method you will give added support to the ceramic or porcelean tile and it will not crack even if you drop an object on it because it is well supported below.

Answer 4

All good answers. The truth, No you do not have to make sure all of the felt backing is removed. As long as you have a clean dry substrate you will be fine. as to the concrete expanding and contracting. This may be true, But, not a problem. Most all of the tile mortars made today are latex modified. This allows for flex of the mortar. ( Mapei ultra-flex ) As to ceramic or porcelain, porcelain is better, as I'm sure you have seen it also cost more, ceramic is fine for residential use, it should out last your home if installed correctly.

Good Luck.

Answer 5

Just scrape the floor and vacuum well. It is okay if its not perfectly smooth. The acid is overkill!

Don't worry too much about cracking. If your concrete floor has been there a few years it will already have settled. Keep a few extra tiles on hand if one should happen to break from a dropped heavy object.

Answer 6

I would check the floor with a long 8' straight edge for any crowns in the floor. Tile needs to lay flat.

As far as cleaning goes, it is a good idea. I'd use a 25% bleach 75% water and go over the floor completely.

Answer 7

dude or dudette, don't do either this time of year. unless the concrete floor has radiant heat it will not be a good install regardless of what anyone else tells you. is the room dry, warm all the time, no moisture whatsoever? then maybe you could but i would wait for june to do this as concrete shrinks in the cold weather and then expands come summer, which will cause the floor to crack. and when you finally do use one of the flex-bond mortars, white or gray

Answer 8

try this test
get a yellow grout sponge ( you're going ot need one anyways )
get it wet then wring it out
wipe it on the floor here and there...
does the water absorb into the concrete?
if it does then you have good bond as thinset will suck into the slab and form a very good mechanical bond, dut still used a latex modifed ( polymer ) thinset.
if the water does not absorb , you still might get a good bond with a polymer modified thinset.
in any event a good sponge pass to clean up the floor will remove any dirt and dust that will interfere with your bond. and you can set in summer or winter as someone else pointed out polymer thinset flex a little so you need not worry about bond loss so as long as your slab is clean

Answer 9

most tilers would say the best method is to get them up and retile. for a valid reason, if the old tiles are not well laid or poorly adhered the stresses of new tiles on top can cause the old ones to come free of the base. quite a rare occurence, but happens. so if its a new customer we point that out to them and the choice is theirs to lift or tile over. use a single part flexible adhesive from a decent store(not b and q) . if your new tiles are of a similar size to the old ones try to start tiling by laying them overlapping the old ones. i:e the centre of your new tile lays on top of the grout line between 2 of the old ones. this helps to spread the tensions.

Answer 10

yes its true cuz any imperfestion you have will mess up the floor. I have ceramic an I HATE it.the house settled and it cracked,my wife dropped a pan and it cracked.Im ready to puul it up and go to wood or regular tile