Anybody have a secret for removing the black adhesive left on a cement floor after removing old vinyl tiles?

Maybe I should be asking whether I actually need to remove the adhesive. Right now the plan is to use 12" ceramic tiles for the new floor.

In fact, now that I think about it I'm really not sure what prep is required to place the ceramic tiles on a slab floor. Should I use cement backerboard?

Thanks... RC

I can't speak to removing the black stuff, but as for a base; in my area we use lauan as the base for tile... but note that it is not recommended in some areas.

Yes, you'll put something down first - to apply the ceramic... and you can be the judge of how much of the old black glue to remove based on how much it makes your lauan stick up.

Perhaps use a torch to soften the biggest lumps of glue and scrape them off. Anything sticking up in the middle of a tile, could cause it to crack under load. You may want to be a little extra generous with the cement for it assuring uniform support for each tile. Ceramic tile has very little give. You may want to fill low areas with floor leveler.

I don't have that much experience with tile, but I don't remember seeing luan over concrete. Not sure how you would fasten it down. I would be concerned about it drawing damp and delaminating or even rotting. It is not quite his area, but perhaps check with Tom (Speedball1) in plumbing.

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Originally Posted by labman

Perhaps use a torch to soften the biggest lumps of glue and scrape them off. Anything sticking up in the middle of a tile, could cause it to crack under load. You may want to be a little extra generous with the cement for it assuring uniform support for each tile. Ceramic tile has very little give. You may want to fill low areas with floor leveler.

I don't have that much experience with tile, but I don't remember seeing luan over concrete. Not sure how you would fasten it down. I would be concerned about it drawing damp and delaminating or even rotting. It is not quite his area, but perhaps check with Tom (Speedball1) in plumbing.

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You don't need cement backer board as you already have concrete as the substrate. Start by sealing any cracks and then use thinset as the base right before you apply the ceramic tile.

Thanks, labman, you may saved me from misleading.

Thanks guys. Looks like I have a fair amount of physical labor in store for me in order to prep this floor for the tile. Fortunately, the floor is fairly level and flat, so all I will need to do is remove the old tiles and glue to expose the concrete surface for the thinset to bond to.

Has anybody ever worked with this Ditra? It looks like a pretty decent product to use for longevity of ceramic tiles... to keep them from cracking. I think I will do a little more research on this stuff, but right now I'm leaning that way on using it. Guess I will still need to remove the old glue prior to installing it.

RC

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Originally Posted by icandoit

Thanks guys. Looks like I have a fair amount of physical labor in store for me in order to prep this floor for the tile. Fortunately, the floor is fairly level and flat, so all I will need to do is remove the old tiles and glue to expose the concrete surface for the thinset to bond to.

Has anybody ever worked with this Ditra? It looks like a pretty decent product to use for longevity of ceramic tiles...to keep them from cracking. I think I will do a little more research on this stuff, but right now I'm leaning that way on using it. Guess I will still need to remove the old glue prior to installing it.

RC

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Sounds like a real plus when used for applying tiles to a concrete substrate. Compensates for the moody behavior of concrete with time/temp. Is it costly? This seems useless when used on a floor with a wood substrate. Is it readily available?

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Is it costly? Is it readily available?

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Two excellent questions, which I must find the answers to.

I'm helping a friend with a similar project, and removing the previous adhesive is difficult/impossible. Did you finally find a mastic that could be installed over the adhesive, or did you find a way to completely remove the dried adhesive that was left on the concerete?

Thanks in advance.

JD

Well, I found out that you can't put the thinset on top of the old mastic. At least, it's not advised. I guess you could but it would be risky since the thinset wouldn't adhere well to the mastic.

So, I've been slowly removing the old mastic. The best method I've found so far is a torch and a razor scraper. It's going to be a lot of work, but nothing else I've found works any better. I tried the boiling water trick but it didn't work all that good. There is a stripper made by Jasco that will disolve the mastic but it makes a big mess and it's not recommended as the dissolved solution will seep deep into the concrete and you will never get it out.

Good luck.

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Originally Posted by icandoit

Well, I found out that you can't put the thinset on top of the old mastic. At least, it's not advised. I guess you could but it would be risky since the thinset wouldn't adhere well to the mastic.

So, I've been slowly removing the old mastic. The best method I've found so far is a torch and a razor scraper. It's going to be a lot of work, but nothing else I've found works any better. I tried the boiling water trick but it didn't work all that good. There is a stripper made by Jasco that will disolve the mastic but it makes a big mess and it's not recommended as the disolved solution will seep deep into the concrete and you will never get it out.

Good luck.

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how about trying removing it with a hot ironer and thin metal plate ( heavy duty aluminum foil may be the best to use; since you already remove the tile)... I swa company remove this kind of tile with something simliar to a hot ironer and they wipe off the residue off with chemical... those black glue do contain asbesto

The iron sounds like a good idea. Maybe try blotting paper as well as the foil.

Interesting ideas. I will have to give them a try.

Thanks guys.

I found using WD-40 and Bounce sheets made the job a lot easier. I just sprayed some WD-40 on the area to work on and started rubbing it into the black adhesive with a used or ununsed (doesn't matter which) Bounce sheet and without much effort the adhesive came right off. I wipe away the liquefied adhesive with a rag and started the next area.