Net Positive Home* | Chicago (*electrical only)

The goal for this residence was to create a home that produces more electricity than uses and is a minimal size to optimize yard space. The reduced size (2800 sq. ft.), tight construction bordering on Passivehaus levels, highly sustainable building systems, and passive techniques combined with a 6.2kW garage mounted PV array were designed to exceed Net Zero levels for its electrical use. The smaller house footprint provided a larger yard, supplemented with a fully developed green roof system. The home achieved a HERS rating of 32 and an EUI rating of 23. 

To provide enough electric power production, the garage was covered with (24) 260W PV panels mounted at their optimal angle. The annual power production is expected to be 7840 kWh and the annual electric usage is anticipated to be 4800 kWh. Surplus electricity will partially charge their electric car. The owners specifically requested that the home have a gas fired furnace, water heater, dryer and cooktop. A larger PV array, which would have fit on the main roof, would have provided enough renewable energy to make the house fully Net Zero in conjunction with using air source HVAC systems, an induction cooktop, and a hybrid dryer and water heater.

While the predominant east/west orientation constrained passive solar possibilities, natural daylighting was obtained through careful window placement and a central skylight from the roof down to the basement. The windows were selected based on orientation specific solar heat gain coefficients and solar shading coefficients. Natural ventilation was achieved by venting hot air out of the third floor penthouse windows while drawing in cooler air from the basement and first floor.


Reclaimed local wood for the cabinets and flooring

Air to Air heat exchanger for fresh air intake

Centrally controlled, smart thermostats

Outside combustion air for the fireplace

Ultra high efficiency mechancial system

Stacked air vent passive system

Water Sense™ plumbing fixtures

Ceiling fans for air movement

Garage mounted solar panels

Low water landscape garden

Cement fiberboard siding

Energy Star appliances

LED lighting throughout

Tight Construction

Green Roof system

Photos by ©2017 Wayne Cable