continuing saga of my floor and a couple questions

Hello,
As some of you have followed I'm replacing a vinyl tiled kitchen floor with porcelain tiles. I had hired a contractor to do the entire remodel but had to let him go because of quality issues.
As an example he recommended tiling right on top of the vinyl tile. I checked this out here and with some professional tilers and the consensus was while it's never a good idea if the vinyl tile is very well set and is of the non-cushioned type you can get away with it. This contractor said that the tile was as well set as he'd seen and that it would be fine to tile over.
Well yesterday (he's gone now and I'm completing this by myself) I was painting walls and a caulk gun fell off a stepladder and chipped a nice sized piece out of one of the vinyl tiles. Thinking this was odd behavior for a floor that's so well set we can put ceramic tile over it I checked it out a bit further and lo and behold the tiles came rather easily off of the floor. This was next to impossible to detect with all the edges and corners down.
So I immediately decided to rip the floor up as was suggested by all but this contractor and while I'm not finished yet so far doing half of it has taken about 2 hrs. This is with a hammer and a scraper, nothing fancier than that. To my thinking if this floor was really ok to tile over it should have taken a lot longer than that. So one fortuitous accident (the caulk gun falling) has probably saved me from laying a tile floor that would have been nothing but a headache.
Ok now the questions
1) This floor is by no means down to clean concrete. There are remnants of some sort of building paper they decided to put down in some places (and oddly enough not in others, this is only a 12x12 room...) and there is old adhesive etc.
Pretty sure I don't want to tile directly over this stuff. I have to level the floor a bit anyway. What's the best way to prep this floor? Skim coat it with leveling compound? Nail or glue hardibacker to it? I'd like to keep the added height to a minimum. Do I have to sand all this crap off? (god, please no)
2) Before I was told I didn't have to use the fiberglass membrane for keeping slab cracks from telescoping to the floor. This was due to the vinyl tile being in place. Well it's gone now so I assume I have to use this membrane product. Should I install that underneath or on top of whatever flooring prep (leveler or hardibacker or whatever) I use.
Incidentally, I have some insight now into the real reason the contrator didn't want to remove this floor. Basically he had done it once and believed he had been exposed to asbestos etc. (This was learned in a rather long not very coherent rant when I told him that everyone had recommended removing the floor.) He mentioned that it would take us 7 days to remove it all and that "he would stake his contractor's license that this floor was ok to tile over." It's taken me 2 hrs to do half of it by hand being careful not to hit the cabinets we shouldn't have installed til after this was done. If I had rented a tile remover removing the whole floor would probably have taken no longer than an hour.
Thanks in advance for the help ml
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The asbestos floor tile is not the flaky, dangerous asbestos used in insulation applications of long ago. As I understand it, the people that came down with asbestosis were exposed to it for a very prolonged period of time.
However, use proper precautions. Turn off your air handler if you have one, wear a breather mask, put a window fan in place in that room to suck air out, open up another window somewhere to create a cross-breeze, put plastic over any doorways, create negative pressure in the room you are working in to help keep dust from leaving the work area... etc.
You can go nuts, but I don't think there is too much danger in removing the old floor tiles. Others will probably disagree with me, but just one man's opinion...
Hey, I just removed 200 sq ft of the old tile using the same precautions and I feel fine! <G>
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On 6-Jun-2005, snipped-for-privacy@optonline.net wrote:

Um, thanks for the info but this doesn't really relate to what I'm doing. The remark about asbestos tile had to do with a job the contractor I had originally hired for the job did some time ago. And most likely there was no asbestos there either.
I just have vinyl tile and am not worried about any exposure issues.
thanks ml
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snipped-for-privacy@yahoo.com wrote:

Hardibacker is not put down over slabs. Have you tried using a razor scraper on the paper and adhesive? As for the adhesive if it's stuck good and next to impossible to scrape you can use modified thinset over it. Read the bag and it will advise if it can be used over cutback and other adhesives. But the adhesive can not be loose and chipping. Razor scraper ad elbow grease. Buy a pack of blades with the tool.
As for level, being flat and even is more important so lay a straightedge on the floor to check for flatness. In many cases you can make some adjustments for minor low and high spots as you tile by backbuttering etc, if the elevations are not to pronounced. Extreme high points on the slab should be ground off. fwiw, floor levelers are generally a pia for the beginner and if their use can be avoided, do so.

Elastomeric membranes work and worth every penny. Especially helpful for new slabs that are in the 'process' of curing. I'm partial to the ECB product, but it must go over a clean floor. It would go down after you use a self-leveler, if you do.
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I'm no expert in terms of the overall floor prep but to remove the adhesive, should you decide to do so, can be done with a strong Methylene Chloride product such as Jasco Glue and Adhesive remover. I'd see how flat the floor is and based on that, remove the adhesive (this stuff will clean the concrete as well of any oils etc...), put down the membrane, and start tiling. If the floor is not flat, well then you've prolly got to go with the thinset route. Cheers, cc

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Thanks for the info. Methylene Chloride is setting of alarm bells in the back of my mind though. Isn't this stuff a major carcinogen? Answering my own question I find this link http://www.hsia.org/white_papers/dcm%20wp.htm which sort of indicates while you don't want to put this on your salad it should be reasonably safe to use occasionally.
I believe I'll try this stuff out if it doesn't cost the farm.
ml
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The Jasco Adhesive Remover and a razor scraper are going right through this stuff. Thanks guys, you rock!
ml
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