In the North American green buildings market, where LEED, BREEAM, WELL, Living Building Challenge, and Green Globes dominate the landscape, the German-born Passivhaus standard (aka, Passive House) has struggled to gain a solid foothold, despite a strong grassroots growth effort among its early adopters.
There are an estimated 60,000 buildings worldwide designed and built to Passivhaus standards, the vast majority in Europe. In the U.S., more than 1.1 million sf of building space is certified or pre-certified to PHIUS+ standards, according to the Passive House Institute US. But the lion’s share is small residential buildings.
A new study conducted by FXFOWLE and funded by the New York State Energy Research and Development Authority set out to determine the viability of Passivhaus for tall residential buildings. The research involved investigating the feasibility of adapting the design of a sustainable mixed-use high-rise building in the 2016 New York City market to Passivhaus requirements. The base case building is a 593,000-sf, 26-story multifamily high-rise building in Queens that is targeting LEED v.3 Silver Certification and 20% energy cost savings from ASHRAE 90.1-2007. The study examined the impacts of achieving the standard from an architectural, enclosure detailing, mechanical, structural, constructability, resiliency, zoning, and code perspective.
FXFOWLE’s findings show promise for the niche standard. The technical difficulties of meeting the stringent energy efficiency and insulation standards can be overcome with minimal aesthetic changes and a glazing ratio of up to 40%, according to the report’s authors, Ilana Judah, Intl. Assoc. AIA, LEED AP, Principal, Director of Sustainability, and Daniel Piselli, AIA, LEED AP, Senior Associate, both with FXFOWLE.
From a financial perspective, the Passivhaus design represents an increased capital cost of 2.4%, a 40-year net present value of $5.2 million, and a payback of 24 years as compared to the base case building.
“The multifamily project type and scale are favorable to meet Passivhaus requirements due to controllable internal heat gains and low enclosure to volume ratios,” the authors wrote. “Some code and regulatory requirements conflict with Passivhaus strategies, and these must be aligned to enable implementation.”