Some people find concrete work mundane. After today, I’m convinced concrete contractors are totally underrated.
Think about it: Somehow, workers manage to wrestle this extremely heavy goop into a form, shove it around pipes and rebar, smooth it down, level it off…all with minimal power-assisted technology. Sure, the truck and pump get the stuff to the site, but it’s sheer muscle, experience, and know-how that transforms the wet blob into a smooth, seamless surface.
Today was a big day for the Portland Live/Work Project: We brought in two truckloads of concrete for the slab; when that truck arrives, there’s really no going back.
Our biggest concern during the pour was the network of PEX tubing tied to the rebar. A web search the night before told me that it wasn’t impossible for a concrete worker to slice the PEX, creating a totally $#!&!-ed situation. Fortunately, all went as planned and the system retained pressure the entire day (you actually “charge” the radiant system with 100psi of compressed air to ensure that there are no leaks).
One of the coolest pieces of equipment was this mechanized trowel (I’m sure there’s a name for it…I called it the “Whirlybird”). This photo tells its story well:
Even with the help of power tools, much of the process requires an expert touch and experienced hand. Still more impressive was how quickly the crew went from pumping concrete to walking across the surface. In about two hours the crew went from pouring concrete to to walking on the surface. Here’s a few more shots and a timeline from the day’s effort.
10:00 AM: Concrete truck arrives and the pumping begins.
10:07 AM: Kip begins hand-troweling at the corner. Other workers spread the concrete and apply trowels as well. We’re relieved that there are few sharp tools that might pierce the PEX.
10:20 AM: The crew begins screeding and troweling in earnest. Large portions of the slab begin to take shape.
11:30 AM: The pour is complete and worker put the final touches with the float and hand trowels.
12:00PM: Workers move out onto the slab and begin smoothing the concrete with a series of trowels.
12:10 AM: Kip and the crew walk on the slab, using both power and hand trowels. This process continues for at least another hour.