Woman-owned architecture firm HPZS has completed the first certified single-family Passive House renovation in Chicago, demonstrating that retrofitting America’s older homes to meet energy-efficient goals is possible and can even be done at a profit.

All of these design decisions resulted in an extremely air-tight edifice with a test score of 0.0596 cubic feet per minute per 50 square feet (an older home built using traditional construction techniques can test up to 120 cf/m). That ultra-low score earned the house three bonus certifications: Zero Energy Ready Home (ZERH) status from the Department of Energy, EPA Energy Star, and an EPA Indoor airPlus label. The renovated passive house is currently slated to be resold on the speculative housing market for profit.
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