Poured a couple of pads this weekend for condensers. The pads are +/` 3 1/2" Thick. Humidity was probably around 60% or better on the day of the pour (Sat), Sunday it was decent until evening, then it rained. Relative humidity today is 85% with possible rain today – Wed. The condenses weigh about 140lbs each. I doubt we will get anywhere with this till next week at the earliest. So that would be set for over a week. I don't need to wait the full 28 days do I?