Using a specialized mixer/pump, workers poured the gypcrete slab which encases the tubing to create the radiant floor system. Gypcrete is a lightweight concrete aggregate containing gypsum (also the main ingredient of sheetrock).
The floor of the North bumpout was physically separated from the rest of the house, in case it is necessary to remove the bumpout for house transport. A small access panel was left uncovered in order to allow the bumpout circuit to be disconnected.
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