On a sweltering hot and humid summer morning last week in Washington DC, PHIUS staff joined community development and design professionals from both sides of the Atlantic on a tour of sustainable social housing. The visit to Weinberg Commons, the first affordable multifamily retrofit project to earn PHIUS+ certification, capped the weeklong DC Energy Future Exchange Tour, organized by the Ecologic Institute.
The tour was led by Koray Aysin of HousingUP with Donna Rosano of Zavos Architecture + Design and Matt Fine, CPHC (formerly with Zavos). The guides described in detail the challenges and creative approaches they applied to renovate a dilapidated group of garden apartments into healthy, dignified, affordable homes for families of limited means—while also achieving ambitious energy and environmental targets. Because the developer, Housing Up, also pays the utilities, they had an incentive to invest in the building’s energy efficiency, knowing that the benefits would exceed the costs down the road. Some of the strategies the team used to hit stringent PHIUS+ energy targets included:
- Specially designed window boxes that block solar heat gain while allowing natural light to enter the dwelling areas
- Outboard insulation applied between vertical joist, a creative approach to a structural challenge
- Energy recovery ventilation that reuses energy from indoors to pre-heat or cool thefresh air stream
- Exceptional air tightness of 0.58ACH 50. This result is remarkable in new construction, and even more difficult to achieve in an existing building
- A Variable Refrigerant Flow system that allows different sides of the building to heat and cool simultaneously. Due to superior insulation and air-tightness, all twelve units in the building are served by just one 2 ½ ton condensing unit—typical of a large single-family house.
- Solar hot water panels and a basement storage tank; this results in a 40% cost savings
- Rooftop solar electric panels developed by a third party, which sells back to the apartment at a rate 50% lower than grid purchase
Attendees were also able to see passive performance in action. While the tour started on a hot, loud street, discussion continued in the cool and quiet of the community room, thanks to the well-executed features. Here, participants learned about the financial aspects of the project. Financing sources included federal Low Income Housing Tax Credits, local housing funds from DC DHCD, funds from the DC Department of Behavioral Health, and philanthropic support.
Check out our Multifamily Resource page for concepts and case studies applying PHIUS standards to affordable housing. Then sign up to join us in Boston on September 20 for a pre-conference workshop with leading practitioners in design and community development.