tile over slab w/ flooring adhesive

I’ve removed the engineered hardwood floor/ over concrete slab.
Before I tile….
do I need to remove the old adhesive on the slab, or leave it as a waterproof membrane??
I’ve removed the engineered hardwood floor/ over concrete slab.
Before I tile….
do I need to remove the old adhesive on the slab, or leave it as a waterproof membrane??
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Replies
remove it..
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
WOW!!! What a Ride!
Forget the primal scream, just ROAR!!!
There are thinsets that are engineered for use over asphalt cutback and other adhesives. Tec is one maker. Go to tecspecialty.com/product _selector_installation.asp . Probably best to go to your tile supplier and see which brand they carry. There are other brands for this app.
finished product isn't any better than what's under it...
why risk an out of pocket at a latter date...
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->
WOW!!! What a Ride!Forget the primal scream, just ROAR!!!
Loosely pertaining to this topic, I was recently at a commercial job site where the tile installers were preparing to lay about 3000 sf of 18" ceramic tile on a new slab...Site was deserted for the holiday so no one could answer my question as to why there were large rolls of something called "non-asphalt felt underlayment" and a number of buckets of floor mastic along w/ the 50 or so bags of Tec Full Flex...Looked to me like they intended to glue down this felt onto the slab and thinset mortar the tiles onto it... Anyone ever heard of this? The stuff looked like vinyl flooring without the vinyl surface. I've never seen or heard of this nor can I find anything by googling it.
Slip sheet or crack isolation membrane.
It allows the concrete floor a little stress without it telegraphing up through the tile.
Makes it alot easier to remove the tile in the future as well.[email protected]
Yea, I guess I knew it was an underlayment for the tile (slip sheet), but I was actually wondering if anyone had ever seen paper felt used this way? I've never even heard of this being an acceptable 'membrane' or underlayment for tile---not in the TCA handbook, nor any of the pro tile books I've read, nor ever on John Bridge's or Michael Dresden's sites/forums.What happens when the paper gets wet? Bond to tile dissolves. Sounds ridiculous to me. Since the installers would be troweling on mastic to glue down the felt, why not just trowel on a REAL crack isolation membrane in the first place...like Tec Hydraflex -----------> http://www.smethursttile.com/surfacepreparation.html
We are both only speculating on exactly WHAT the material was and what it's useful applications are.
And forget about that handbook for a minute. And then tell me how that underlayment is going to get so wet that it disintegrates?
I've laid floor tile over tar paper that wasn't glued or fastened and it held up to commercial foot traffic for many years. It's commom practice in tile and kitchen showrooms and makes it easy to tear up and replace.[email protected]
Well, the building was to be used for office space and climate controlled storage. The floors are undoubtedly intended to be permanent. Else, no tile (especially expensive, large format porcelain) would be laid at all...painted or sealed concrete and commercial glue down carpet are the obvious cheap 'temporary' alternatives.If you're only speculating as to what it was, then you've never seen or heard of it's application either, I can assume.. Again, it's PAPER felt, specifically called "non-asphalt paper felt underlayment" on the label. I've never mortared anything to paper, but I can't imagine it would be a decent, durable substrate for floor tile, can you? Which is why I asked.
What's the diff between a layer of old adhesive covered by the proper thinset ... and a layer of ditra? Both are membranes between the tile and the slab."Put your creed in your deed." Emerson
"When asked if you can do something, tell'em "Why certainly I can", then get busy and find a way to do it." T. Roosevelt
I would call Mapei tech support ans see if the recommend one of their product for the said application.
I disagree with Imerc.
[email protected]