As planned, Mario (our concrete mason) came out on Monday of last week and put in the plastic vapor barrier and the wire mesh on top of the foam insulation. Over the weekend I installed “J” bolts (they’re shaped like J’s) where our interior walls will go, so we don’t have to drill or nail the new concrete slab. I cut short pieces of steel rod and stuck them into the foam and then wire-tied the J bolts to them to keep them positioned and upright.
Today Lester, our radiant heating contractor, came out and installed the PEX tubing that will eventually allow hot water from the boiler to keep our concrete slab nice and warm and heat the whole basement. Once the tubing loops were run and zip tied to the mesh, he pumped compressed air in to 70 psi as a pressure test to ensure the loops are air (and water) tight. They’ll stay pressurized during the concrete pour and cure to make sure they don’t get squeezed anywhere. He gave me a list of warnings to pass on to Mario and his guys when they’re pouring the concrete: when they’re using a concrete spreader, don’t hit the tubing! When they tip up a wheel barrow, don’t hit the tubing! When they’re running wheel barrows back and forth, lay down some half-inch plywood so they don’t hit the tubing! I sensed a trend.
Mario is planning to pour the floor on Thursday, and I’ll be there making sure that Lester’s instructions are followed. If anything happens to the tubing during the pour and it leaks, our whole radiant-heating plans will crumble. The only choice would be to tear up the whole brand new concrete slab and start over, or switch to hot water forced air in the basement, and with the lack of head room I don’t want to run ducting!