[masraum]

I think you could get away with it (but it would require a lot of work), but I think it would be better if you didn't.

I think you would need to seal the hell out of the grout, use very thin grout lines. We had tile floors in our old home 1st floor only about 1000sqft. After years of family and pets, the grout looked horrible and it was a fairly medium shade and tone. My wife found some "grout paint" that was great and seemed in the time that we were in the house to be essentially waterproof.