Concrete floor preparation for carpet

Hi If its level: Very little prep just allow to dry or don't allow it to be saturated if your not ready to carpet yet (sounds like your'e not quiet). If its out of level : Same as the above but lay a self level screed across the floor and allow to dry prior to carpeting.

it's a general rule of thumb to allow 1mm per day up to 50mm deep and anything over double that time for natural drying, the laitence will need to be mechanically removed first (your builder may have done this but it seems to be unusual for them to complete their job and leave the customer to do it) then a rh% test is to be taken it must read below 75% rh for carpet to be installed if it's higher you will need a surface dpm and a floorlayers screed, please check what products the builders have used first it makes a difference to the products which can be used afterwards. 9 times out of 10 you will need a surface dpm and screed so please factor that into your costs, rh% testing takes a minimum of 72 hours to get a reliable reading and involves drilling a hole into the concrete and inserting a sleeve to collect residual humidity levels before measuring it with a probe, this should be done by your flooring professional but you should expect to pay for their time and the use of their materials (considerably less expensive than buying a £1000 worth of testing equipment).