Radiant heat tubes, pipes and conduits for water, waste, propane and electricity, the vent for the stove, and everything else that needs to travel through the floor have been placed into the foundation footprint, ready to be entombed in concrete. The wire mesh will keep everything in place when the concrete is poured. The pink foam insulation will keep the heat circulating up into the house instead of traveling down into the pea gravel & dirt below.
Looks like a lot of work to set up, doesn't it?
Here's a close-up of the Tube Junction for the radiant heat. When the house is finished, this will be in a small closet under the stairs, accessible from the bathroom. The rest of the apparatus will be in the Mechanical Room on the other side of the wall. Pressure gauges are cool.