Shows 6 mil plastic sheeting & 2″ x 4″ s, studs with temporary rain guard on the north west end of B.B.S.  corporate offices being built . Concrete has been poured on that north west corner . The plastic is a temporary covering , so when the  concrete is drying . Just in  case it would start raining . If, cement  gets wet when drying ,it will  leave  rain droplet marks in the concrete with a little bit of rain,does not hurt the cement & helps cure it. But if it rains hard the concrete would leave ugly marks and  the concrete would have to be finished again . That,s if a smooth floor is wanted  ? This is for fresh poured concrete …