How Passive House Benefits Affordable Projects

Andrew Bourne

The Passive House movement has accelerated under its own power in the United States, driven by increasing efforts to improve energy efficiency and reduce greenhouse gas emissions from buildings and plants where energy is produced. With the passage of the $700 billion Inflation Reduction Act in August, Passive House is likely to move even further into the spotlight.

To date, the affordable housing component of the multifamily market has lagged behind. Hesitancy to employ passive building’s strict energy efficiency standards in affordable developments primarily lies in the added upfront cost, which typically ranges from 3 percent to 7 percent of the total project cost. A second challenge is the fear of the unknown. Affordable housing developers aren’t turning to Passive House techniques because their designers, contractors and other professionals are not experienced in using them.

The Inflation Reduction Act, which the National Housing Trust says provides $25 billion in funding for affordable housing, may be the boost needed to expand the use of passive building further into the affordable and workforce housing sector.

The cruel irony of the slow acceptance of passive building in affordable housing is that the myriad benefits of its energy efficiency standards resonate even more in these types of projects. The following discusses a few of these benefits.

Lifecycle Energy Savings

Estimated savings vary depending on the source and the climate in which the building sits, but studies across all geographies and building types show staggering energy savings in Passive House buildings. For example, a 2021 study led by the New York City Department of Housing Preservation and Development found that Passive House projects yielded energy savings for building owners and tenants ranging from 28 percent to 68 percent. This reduction in the cost of utilities for building operators and residents contributes substantially to the overall affordability of a multifamily property.

Comfort and Quality

Affordable and workforce properties still face the stigma of being somehow “less” than their market-rate counterparts in comfort, quality, aesthetics and certain other livability measures. Passive House properties flip that script. The super-insulated buildings in pre-certified and certified properties feature increased thermal, air and radiation control. This provides a home free of drafts and hot and cold spots while reducing sound transmission. Passive House units are incredibly quiet, which is particularly relevant in affordable developments in low-income urban communities where the surrounding area may include highways, trains and busy commercial districts. The high-performance, triple-glazed windows assist in that noise mitigation and use solar heat gain and low U values to reduce heating costs in the winter and minimize overheating in warmer seasons and climates. Heating, cooling, and ventilation technologies ensure excellent air quality and moisture control for maximum resident comfort.

Funding and Community Acceptance

Photo by Wikimedia Commons

Because affordable developments typically rely on government funding, a commitment to Passive House standards can bolster the case that the project is worthy of receiving the requested grants and loans. Also, community opposition to affordable and workforce housing properties can be substantially muted for a development committed to high-quality standards and energy efficiency.

Tips & Lessons Learned

Not all passive building projects achieve the level of Passive House certification, which requires meeting rigid standards set by governing bodies such as the original PassivHaus Institut (PHI) in Germany, founder of the technique in the 1990s, and its U.S. counterpart, Passive House Institute US (PHIUS). A building may adhere to all or most of the standards, but either not seek or fail to complete the full requirements for certification.

Dakota’s commitment to Passive House began in 2016, and since that time we have learned a lot.

Experience Breeds Satisfaction

Most contractors encounter a learning curve in their first Passive House building or two, but then the “new” details become second nature. Ultimately, most trades enjoy working to overcome challenges that arise, embracing the process and developing ways to help reduce the front-end cost increase. Many even see reduced costs during the warranty period because of the multi-layered inspection and testing process. The answer is to educate and incentivize by providing property tax breaks, bonus points in the LIHTC application process or a basis-point contribution toward the permanent loan. The more that project team members use Passive House techniques, the more comfortable and confident they become in the process.

Product Specs Can Let You Down

In one of our projects, the specified windows indicated that they were compliant with the pre-certified design, and the vendor reaffirmed this. When they were put to the test, however, they didn’t live up to the requirements.

Designer Expertise and Acceptance is Key

It can be difficult to dissuade an architect from their creative vision, but many aspects of the Passive House approach are non-negotiable, and there are numerous pitfalls on the way to certification. In one case, an architect insisted on cantilevered patios, which required breaking the seal of the building envelope. Ultimately, this detail was a primary contributor in the inability to certify the project. This is why using a design and construction team with a collaborative approach, and an understanding and absolute acceptance of Passive House principles is pivotal. A QA/QC consultant with a similar outlook can also significantly smooth the process during design and construction toward certification.

Affordable and workforce housing projects should show no discernable difference in the way the buildings appear from the outside, or the way that the residents experience living in them. One major step toward achieving this is to commit to the demanding, but ultimately worthwhile Passive House standards in multifamily developments across all income levels.

Andrew Bourne, CPHB®, is director of Preconstruction for Dakota Partners, a developer and constructor of affordable, workforce and market-rate properties in New England, the Mid-Atlantic and the Upper Midwest. He is a PHIUS Certified Passive House Builder.