The guy is coming to pour our finished downstairs floor end of this week. Upstairs (on concrete slab) was poured over 2 months ago and seems fine. Of course - we are hoping (but won't be end of world if not) to be in for Xmas. To this end, he suggested adding an additive to the concrete which 'dries it out faster' and can lay whatever on it in 8 days!!??? We have semi-solid and tiles picked for all downstairs. I am dubious about this when I read about the time it takes to dry out naturally. Any thoughts????