Case study of a DOE Zero Energy Ready home in Ithaca, NY, that achieves a HERS 56 without PV or HERS 15 with 4-kW of PV. The two-story, 1,664-ft2 home is one of 17 single-family and 4 duplex homes built as part of an energy-efficient cooperative. The homes have very simple designs and achieve the Passive House Standard with double-stud walls filled with R-22 closed-cell spray foam plus R-30 blown cellulose, coated OSB sheathing, 5.5-in. foil-faced polyiso under the slab, polyiso-insulated foundation walls, triple-pane windows, an ERV, and passive solar design with electric back up heat.