Peabody Architects guides affordable multifamily development to PHIUS+ 2015 Passive Building Standard Precertification

model image update

A WUFI Passive energy simulation of the Washington Square Town Homes project.  Such models strip away the articulation of a building’s skin and focus on the basic thermal and airtight boundary which directly affect its energy balance.

The design, consultation and pre-development team has been hard at work for over eight months to deliver one of the Passive House (PH) projects awarded in the 2015 round of Low Income Housing Tax Credits (LIHTC) through the Pennsylvania Housing Finance Agency (PHFA).  Of the 40 awarded applications for the 2015 round, 7 of those development projects have targeted Passive House energy performance standards.

The Washington Square Town Homes project, for which we serve as Certified Passive House Consultants (CPHC®), comprise (4) buildings, including (12) townhouse units and (42) walk-up apartments.  The project is to be located within the Borough of Chambersburg, PA where the need for quality, sustainable affordable housing is great – just as it is throughout the DC metro region.  PIRHL Developers and Contractors of Cleveland, Ohio are the Developers and Builders on the project.

eave sketch

One of our primary tasks on this project is to “demystify” what it takes to deliver a Passive House.  Simplified sketch mark-ups serve as one of many tools to bring teams to common ground.

With the knowledge that this is an ambitious undertaking, we are proud to have crossed two very important thresholds on the delivery of the project.

Just recently, we have obtained precertification for PHIUS+ 2015 Passive Building Standard of all 54 dwelling units.  This project currently stands as one of less than a handful of multifamily projects in the U.S. to achieve this.  This status is obtained as a result of our WUFI Passive energy simulation meeting the climate-specific energy metrics and having coordinated building envelope design, detailing, specifications and HVAC systems.  PHIUS provides a comprehensive quality assurance review of DD-level drawings and back-up documentation to confirm accurate WUFI modeling and risk- free building science.

To add to this, the project has now been bid competitively by subcontractors.  In the process, we helped lead a day-long prebid meeting where the project (and largely, the concept of PH) was introduced to interested bidders.

pre-bid mock-up

With the assistance of 475 High Performance Building Supply in the mock-up construction of a 4’x4’ sample wall panel, we were able to fully describe the building envelope system to contractors.

SPFI Southeast    therm footing


Delivering a Passive House building envelope does not require new technology.  It only requires thoughtful design, committed coordination, informed building science, and well-executed construction.  Studies of solar exposure and paths along with thermal bridge modeling and analysis are all part of CPHC® responsibilities.

We eagerly await the results of the bidding process to see where the numbers land within the next few weeks.  Construction is due to begin this summer.

Even after nearly 10 years since PH has come to the U.S., it is true that work such as this is still to be categorized as “pioneering”.  We know, firsthand that large scale Passive House development requires a committed developer, design and construction team.   Having learned from past projects and as well as case studies around the country, we also know how reachable and repeatable these projects can be.  With this in mind, it is our belief that Passive House multifamily must be recognized as the rule rather than the exception by our state and local governments to create high quality, sustaining, and ultra-healthy housing developments.

As evidence to what we see the uptake to be shortly, PHIUS has just introduced an online resource for multifamily developers to better understand the process, criteria and benefits to Passive Building certification.