Howe much postage to send a postcard from US to Canada? As of September 2014, it costs $1.15 to ship a post card  internationally. If it exceeds 4 3/4 inches high or 9 1/4 inches  long, you will be charged the First Class Mail In â¦ ternational price. + 3 others found this useful.
Concrete is never truly done curing, but the minimum wait time should be 28 days. A slab typically cures at least 80% during that time. I suspect the manufacturer is asking you to proceed cautiously to avoid a lawsuit. If you (or your client) can wait that long, then wait the 120 (or more) days. But I wouldn't put any flooring on it inside a month.
This then prevents the slab from drying preparatory to flooring installation. An untreated slab with no. moisture from or to below will take 60 to 90 days to adequately dry at 72 F and 50 % relative humidity. There is. usually adequate time to dry in new construction. Curing compounds or cold weather can slow this process.