It doesn't make sense to me to give ANY warranty at all... whatsoever!
This might not be positive. Basically, they have filled in a weak material with another weak material. Since the cohesive strength of waterborne coatings is generally low, the odds are usually better if the coat is thinner if you are applying a non-pervious (non pourous) coating over the top. It's kind of like those flaky biscuits. The taller it is the more likely that it is beginning to split in the middle. You'll notice that the buscuit is pretty well together up to a certain height... it kinda works the same way for strength... but not exactly. Basically, if you have a material with low cohesive strength then the thicker it is the greater the odds (an opportunities) that it will fail cohesively. Did I explain that in a way that makes sense to you?
Ummmm... I LOVE biscuits!!!
There are a BUNCH of products called Iron Coat from many manufacturers. Which exact product are you talking about. When you say you 'burned the basecoat a little' what exactly did you see? I'm guessing that you are using a solvented product?
Last, here is what I think could happen:
You've got a porous coating that has been applied. As the water made it's way out of the coating (coat #1) during the evaporation phase it left (at best) a microporous substrate. Then, if coat # 2 was also a waterborne (especially a low solids one) then the same thing happened. While some of the original pours may have been sealed, it is likely that not all of them were sealed. Then, depending on the molecular weight of the polymer, it is unlikely that any of the smaller pours were filled because (in general) those products have a surface tension that is too high to fill something small. At best, if all the stars line up in the sky just right, you've got one microporous coat with pours traveling from the top of the coat through the coating to the concrete; then, you've got a second coat with a microporous network traveling from the top of that coat at least through the coating to the first coat. Whhhewww... that's a mouthful to write... just digest that for a moment before continuing... sorry this is so long...
Sooo.... If you are going to then put an impervious coating over the top of that, this floor will get sealed. IF there is hydrostatic pressure under that coating, it is likely escaping without putting a whole lot of pressure on the 2 coats of waterborne with weak adhesion and cohesive strength. Those products don't need much adhesion since pressure is relieved through the porous network. Now, when you seal this, the pressure has no where to go.
If you've ever seen a pressure cooker then you could (kinda) equate the impervious coating to the pressure regulator that is placed on top of the vent pipe (pours). The pressure regulator is a heavy cap that fits over the vent pipe of the pressure cooker. The weight of the pressure regulator determines how much pressure the pot can have in it before it blows the pressure regulator off so that steam can escape. As long as the pressure in the pot is low the regulator will stay put. So, once you block those pours with an impervious coating the pressure underneath is going to build.
So, the big questions are: Does coat # 1 or #2 have high enough adhesion and cohesive strength to hold in the pressure? Will coat #2 delaminate from coat #1 and will it be obvious or will it look like your material delaminated from the old material????? Unless the colors are the difference of night and day it may be very difficult to tell.
So, my advice is... don't mess with this job. Even if you don't give a warranty there is always a bad taste when projects don't go as planned. Many times customers forget that 'you told them so' and will hold you accountable even if you have things in writing. While you would win in court if you had things in writing, there is no way to win when the customer is 'bad mouthing' you to someone when you aren't around to defend yourself!
So... Run Forest... Run Forest... Run!!!
