With the first floor somewhat complete, the majority of the work is being put into the ground floor. Those light blue blocks are these special styrofoam blocks that build like legos. You spread them out, stack them up, lock in rebar in the middle, and then fill them with concrete. They provide an amazing insulation rating, and are very easy to work with. The house, when it is complete, should be about 4000 sq ft, with a huge deck and front porch.