the flooring installation has begun. the black gooey stuff in the photos is tar. yup, tar on the floor. because this is a single story home, the solid hardwood flooring would buckle if it was directly installed on the concrete floor, which is a porous material. therefore, the technique of screeds embedded into a tar covered floor is used. the tar is heated up to a high degree to make it more viscous, and poured directly on the slab. once the tar begins cooling down, the screeds, made of 2x4, are placed into the tar. once cooled, the solid hardwood floor is nailed to the screeds. this technique creates an air cushion between the slab and the floor, therefore enhancing the thermal break of the house. in the meantime, don't breathe too heavily since this tar can be extremely smelly!