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Help. Granite didn't adhere to mortar

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bczoom

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We installed new granite tiles (12x12") on a new kitchen counter.

We laid new hardy-panel concrete backer board underneath (and the mortar is sticking nicely to that).

The mortar didn't seem to stick to the granite. We did use the mortar that's supposed to be used for granite and marble.

Well, with just nominal lifting/pressure, the tiles are popping off.

Any ideas on why? Any ideas on how to make them stick (some different bonding material that won't bleed through to the surface)?

Prior to installation, the back of the tiles were sealed with "Aqua Mix Sealers Choice Gold". Would that cause the tile not to adhere to the mortar?

Help needed/appreciated.
 
bczoom said:
Prior to installation, the back of the tiles were sealed with "Aqua Mix Sealers Choice Gold". Would that cause the tile not to adhere to the mortar?
Click to expand...

I wonder if that's what did it?
I never heard of sealing the back of tiles.
 
I'm no tile expert either and didn't sleep at a holiday inn either.

I'm just about to start my first tile job and wondered why you would seal the back of the tile?
Isn't that to prevent stains and stuff from sticking to the top when it is applied after you are all done the job?

tom
 
From what I know the backs of the tile shouldn't have been sealed, i would suggest (1) sanding the backs of the tile to remove the sealer or (2) etch the backs of the tile, don't know what to recommend, never worked with granite. As bad as I hate to say it, I think you are may be back to square 1 and you may have to remove the mortar bed. Check with the tile place about etching.
 
Get rubber gloves and muriatic acid to clean that stuff off the back of the tile. That sealer is for after the tiles are set and grout is dry. you will need to clean off the thinset and start over with new.
 
OK, I've been on the phone since posting. Mrs. Zoom opened a forum account and posted on a tile forum.

As mentioned by members here, sealing the back of the tile was a no-no.

I talked to the mgr. at Home Depot who agreed and is now trying to figure out how to make it right.

For the heck of it, I called the credit card company to check on buyer protection. Well, if it's something attached to your house, it's not covered.

Tom - She was told to seal the back so not bleeding came through from the back. I didn't think about it but now don't see how mortar would bleed. Silicone, maybe but I doubt mortar. She just did what she was told.

Dave - the mortar has set. Hard as a rock and stuck perfectly to the backer board.

Bill - I've always liked muriatic acid for concrete. If I apply it to granite, is there anything that may bleed through to the front?

I'm thinking sanding, acid and using a wet saw or something to etch the back of the tile may be the solution. I will have to do a full tear-off and start over.

I knew this was going to easily... A day to remove appliances, sink... tear off the old ceramic tile top, a trip to the store then new plywood and backer-board. Another 6 hours on day 2 to cut all the granite, mix mortar and install.
Day 3, put appliances and sink back in and prepare to grout then POOF, SHTF and it's time to start all over again :(
 
bczoom said:
Prior to installation, the back of the tiles were sealed with "Aqua Mix Sealers Choice Gold". Would that cause the tile not to adhere to the mortar?
Click to expand...

Yes. Your thinset needs to adhere to your tile. That is why there is a difference between thinset and grout. I'd contact a local tile company about what you can use on the back side of the tile. A acid wash of some sort maybe?
 
Not sure if just sanding is going to remove the sealer, as granite is porous, and it may have migrated through the surface (which the sealer is supposed to do). Since the back side of granite is rarely polished, this rough surface makes for better adhesion for the thinset, as well as a higher porosity for liquids. Try sanding one to see how deep the sealer actually went in, and take it from there before re-committing yourself to the entire process. If you get back to a very dull finish, you may be where you need to be without involving muriatic acid, as that's nasty stuff if you are not familiar with proper handling of it. BUT, be sure to do a test piece to confirm the process has worked.

FWIW, most (not all) of the people who work in these big box stores learned about the products they sell from the consumers. While there are a few true "professionals" who retired from the trades, most are simply retail employers on OJT. When in these stores I often hear an employee giving wrong information to a customer, and I stick my nose in and correct them so the customer does not end up where you are today. it really pisses me off that they put people on the floor with little more than cursory knowledge of the products they sell. After 35+ years of doing this stuff, I've forgotten more than some of those people will learn while working at Home Depot and Lowes.
 
JEV said:
After 35+ years of doing this stuff, I've forgotten more than some of those people will learn while working at Home Depot and Lowes.
Click to expand...

35 years?! Damn! After doing about 5000 sq ft worth of a mix between ceramic and natural stone I felt like I'd rather walk the plank than do it again. :sad:
 
Had a similar situation some years back and we used a palm sander with course sandpaper fitted and scuffed up the backs...worked for us but i am not familiar with the sealer you have used...but worth a shot.

And if the supplier told you to do it this way then he miss informed you and is liable.
 
Still waiting to hear from Home Depot.

Another question as it's related. I haven't tried yet but what if some tile are actually stuck to the mortar. Any techniques on how to remove the tile without damaging it? They're kind of pricey at $50-90 per sq/ft so we don't want to have them get damaged and have to buy new ones.
 
if some are stuck you could really be in the shit....trying to lift them fragile suckers it not something i would like to encounter.....i will ask around but this is a tough one.
 
I recently remodeled our utility room and had to remove some partial tiles that were adhered to the floor. I used a stiff, 4" putty knife with a beveled edge, and was able to pop most of them without damage. It didn't really matter, because they were getting tossed anyway, but they came up pretty good. Start in a corner, tap the knife under the tile an inch or two, then go to another corner doing the same. Slight upward pressure in the middle of the tile will often release it once the sides are relieved.
 
The mgr at Home Depot called. He talked to some of their reps to get a fix.

The sealer is acrylic based. Using an acrylic based mastic will make them stick. He's going to try it there at the store to make sure it works. If so, they'll give us the mastic and new backer board so we can re-do it. Let's hope this works...
 
I have been reading that many folk prefer to use clear silicon adhesive for this type of job...stain free on the Marble...and silicon sticks mosts things down pretty damn good....and even though sealed it should not be a problem.
 
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