Additive for concrete floor

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????

Ana,

Just a quick question, what price did your guy quote ye for your floor, i'll soon be at the stage for screeding and i want to gauge what a good price is.

On your question even though the screed is not structural, i would still leave it for atleast two weeks for it to dry, if you have underfloor heating even longer, as the if the screed cracks it could tear or crack any pipes in the screed.

When cement and water are mixed the process is a chemical reaction which causes it to harden rather than it actually drying out. Different chemicals can be added to the mix to do different things, such as causing it to harden slower or quicker. I suppose the fact that those of us in the industry call the process "drying out" rather than hardening is misleading! Bear in mind that additives cost money so I'm sure your man will charge accordingly; get a quote for this additional work. Hope this helps.