Did you know that leather and concrete are not compatible? The workmen on the Mansion all change their footwear to high rubber boots for the basement concrete work. The original Executive Mansion's basement floor was three different levels. Mike Wescott, project manager, relates the basics to Bob, on leveling off the floor.
To create a single level for the entire basement floor, close to 60 yards of concrete will be poured. First 4 to 6 inches of crushed stone for drainage is laid down. Next comes a poly moisture barrier, and then 6 inch by 6 inch #10 wire mesh reinforcement is placed down. Before the concrete sets up, the wire gridding will be rasied so that it rests in the middle of the pour to minimize cracking. Additionally, rebar laid out in a "V" shape in all the doorways to help prevent cracking in those areas.
After the gridding is pulled into place, the concrete is leveled with a long 2 by 6 screed, and periodically checked for levelness with infrared beams.