cutback adhesive with asbestos

Discussion in 'Floor Preparation' started by leaf, Apr 28, 2015.

  1. leaf

    leaf Active Member

    Hi. My end goal is to end up with a smooth concrete floor. My problem is that I have cutback adhesive (black mastic?) with asbestos in it so grinding it is out of the question. I've seen that removing it chemically with, say, bean-a-doo leaves a residue that compromises the adhesion of whatever you put on top of it. However, I've never seen anyone address laying a skimcoat of concrete over this type of scenario.
    Would a skimcoat of concrete adhere to a slab floor that was cleaned chemically?

    I've had a floor pro say they would just put two coats of bonding agent over it and then a skim coat and a microtopping over that. However, the cutback adhesive that I'm dealing with has tons of joint compound dust, splotches of dried joint compound and a lot of spilled drywall primer. It looks like a disaster because I've been working on the walls for a while now. So I'd have to clean the cutback before putting bonding agent over it. I tried cleaning it with water and a scrubber but it just wetted the dust and caused it to turn to paste and then dry in the little grooves of the cutback adhesive.

    Thanks in advance for your advice!
  2. Tom Frykman

    Tom Frykman Pro Member

    Are you certain it contains asbestos? There's no way to tell unless it's tested. Relatively inexpensive.
  3. Bud Cline

    Bud Cline Tile Expert Charter Member Senior Member Published

    Clean up the mess you've made with your compounds and then skim-coat the floor with something like Mapei Plani Patch, it's done all of the time to encapsulate cutback adhesives . Not sure where you are getting some of your information but you are somewhat mis-informed.
  4. Mike Antonetti

    Mike Antonetti I Support TFP Senior Member

    Your wanting the "concrete" look for your wear layer? Usually ridges are removed to just a stained from cutback appearance. Then you choose what product you want or get guidance from a decorative concrete contractor.
  5. Incognito

    Incognito No more Mr. Nice Guy! I Support TFP Senior Member

    You will need to wet scrape all the BS you've splattered over the existing adhesive. You should wet scrape the trowel ridges of the cutback as well. It's LEGAL and safe to do so. Confirm that with your local/state online resources.

    Primer is always a good idea. We don't use it on commercial jobs unless the specs call for it. CLEAN properly, and in your case that will involve a lot of mopping and rinsing. Let it dry AT LEAST a day+ with proper ventillation.

    Something like Ardex Feather Finish can be applied directly over cutback. Usually two coats is ideal. If I had to guess I'd say it's around a million square feet or so of cutback that I've covered with patch.

    What are you planning to install? That does make a difference. With more expensive and more sensitive materials the rules change. I'm talking above about tens and hundreds of thousands of yards of relatively CHEAP commercial products like VCT, glue down rug and carpet tile.

    Rubber, wood and linoleum demand quite a higher standard for floor prep because of the RISKS of failure can be so damned expensive to an installer. There's not enough in the labor to RISK any failure whatsoever. We have to do it right the first time.
  6. hollywood

    hollywood Pro Member

    Duraamen products have a product that will work in this situation for a smooth concrete look, it's called Skraffino. Concrete resurfacing interior | decorative concrete overlays, micro-toppings | Duraamen It comes in grey or white . I have talked with the owner of Duraamen and he was helping me with application of Skraffino over gypcrete, he had mentioned that it can be used over cutback adhesives need at least 3 coats of primer first. They have 3 grades regular, fine and super fine depending on the desired look. I would call and get specific instructions on application. They do have installation videos on their website .
  7. Bud Cline

    Bud Cline Tile Expert Charter Member Senior Member Published

    Where does it say that?
    Are we talking about creating a wear-layer or just smoothing the floor to receive additional floor covering materials?
  8. Mike Antonetti

    Mike Antonetti I Support TFP Senior Member

    After I posted, I saw the topic was in carpet section, so I suppose carpet is going over.

    But when Leaf posted, the end goal was smooth concrete floor, I assumed concrete finish(polish, stained?)
  9. leaf

    leaf Active Member

    Thanks for all the advice!!

    I'd like the end product to be a smooth, concrete floor.

    If I understand correctly, I'll need to clean up the mess of drywall dust and spotches that is on top of the cutback adhesive instead of removing the adhesive.

    Can I leave the wall primer splotches on the cutback adhesive or will I need to get those off too? If so, how?

    Also, does concrete adhere better than tiles? In other words, is it less problematic to do a concrete finish than to try to put tiles in over the cutback adhesive?

    When you say put 3 coats of primer over it, what kind of primer?

    Yes, smooth concrete and probably stained.

    Thanks for the advice. My info is coming from surfing the net. I saw a video where they cleaned off the cutback adhesive with bean-a-doo chemical stuff and then layed concrete over that. Then i read how the chemical (especially soy based stuff like bean-a-doo) leaves a residue that severely compromises adhesion. Any thoughts on this?


    Well, I'm not certain but the tiles were 9 inches and the house if from the 1960's. How do I go about getting it tested?

  10. Mike Antonetti

    Mike Antonetti I Support TFP Senior Member

    Absolutely correct. Leaves nothing for the chemistry of cements to grow like crystals and lock into slab. Just another of many "bond breakers"
  11. Bud Cline

    Bud Cline Tile Expert Charter Member Senior Member Published

    And all of this information is coming from DIY'ers that don't know any more than you do at this time is this correct?

    If you want to finish up with a concrete surface to be used as a wear-surface then disregard everything you have been told here so far. To end with a concrete wear-surface is going to require some different techniques and products. Start with scraping the cutback down to the point that it is nothing more than a stain.
  12. leaf

    leaf Active Member

    I hear you loud and clear about the DIY info. Would you happen to have any advice on how to scrape away the cutback adhesive efficiently. I did a 1 foot squared patch and it took about a half hour and one blade. I've got my whole three bedroom house to do. What are your thoughts on just getting it up with a chemical. It squeegies right up.
  13. Mike Antonetti

    Mike Antonetti I Support TFP Senior Member

    Well if there is no carpet going over this, then it is in wrong category, I'm still not sure.
  14. Bud Cline

    Bud Cline Tile Expert Charter Member Senior Member Published

    The use of chemicals to remove the existing adhesive may result in the compromise of any additional products you may try to bond to the substrate.

    I use a 3-4 inch long handle (18") wallpaper scraper and a lot of blades.
  15. hollywood

    hollywood Pro Member

    Did you go to the website of Durramen Products? Scrape floor like Inconito and Mr. Cline have suggested for your floor prep .Durramen cp 1000 primer 3 coats is what you need, then you will be able to start your micro topping installation. You will need all 3 Skarffino products reg, fine and super fine for a smooth topping. You can add intergal color or add color after install. You will most likely need to invest in some tooling , rent a swing machine for screening but cost shoul be minimal. They post videos on how to do the micro toppings. It does take some skills and techniques but if you are willing to put some effort you can get it done. And I'm not a diy'er.
  16. Chris Mha

    Chris Mha Charter Member Senior Member

    Bud, Hollywood is far from a diy'er. He does this for a living in L.A..
  17. Bud Cline

    Bud Cline Tile Expert Charter Member Senior Member Published

    Don't go nuts Chris, I wasn't referring to Hollywood's comments as the chronological order of the comments would attest to.

    I was referring to the conclusions drawn by the OP early in this thread. Now that things have become slightly clearer I too made a reference to using Plani-Patch that should now be considered mis-information and void.

    Hollywood is on the right track.:)
  18. Chris Mha

    Chris Mha Charter Member Senior Member

    Sorry Bud. My bad for misinterpreting your post. Me go nuts? I'm in the flooring business I can't help but to be nuts
  19. Bud Cline

    Bud Cline Tile Expert Charter Member Senior Member Published

    We all have to be a little nuts to stay in this field for decades.:yesss:
  20. hollywood

    hollywood Pro Member

    Where's the Amen button?

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