Revive Properties and Philgreen Construction built this 1,533-square-foot multifamily project in Fort Collins, Colorado, to the high performance criteria of the U.S. Department of Energy Zero Energy Ready Home (ZERH) program.

The builder and developer achieved a HERS score of -8 on one of these 1,500-square-foot townhomes, thanks to the homes’ compact efficient design and roof-mounted solar.

The mostly mono-planed roof design provides more space for solar panels.

ENERGY STAR appliances, LED lighting, and EPA WaterSense-labeled plumbing fixtures add to energy and water savings.

Spray foam and rigid foam were used under the slab while rigid foam wraps the exterior of the foundation walls.

The walls were constructed of 2-by-4 studs staggered on 2-by-6 plates, providing space to weave insulation in between the studs and forming a continuous thermal break through the wall. The blown fiberglass provided R-23 of insulation.

The walls were sheathed with a coated OSB. When taped at the seams, this sheathing can take the place of house wrap to provide an air- and weather-resistant barrier.

Rim joists were insulated with R-20 of open-cell spray foam.

The underside of the roof deck was insulated with R-50 of open-cell spray foam, providing a conditioned space for the HVAC ducts. Heating and cooling is provided by a 3.6-COP ground source heat pump.

During construction, all of the homes are prewired for electric cars,