The Passive House concept continues to scale up in North America, in both number and size of projects. Passive House buildings benefit from airtight construction, as minimizing winter infiltration directly lowers energy consumed when heating the building. Airtight construction also hinders airborne moisture from escaping through the building skin, thus requiring new thinking about the requirements of the ventilation system.

Transforming existing buildings is especially challenging with public-owned affordable housing buildings that rely on public funding and grants and must continue to house residents during major renovations. This session will share the successes of the Cambridge Housing Authority (CHA), which in 2014 vowed to reduce energy intensity by 20% in a decade.  CHA met that goal in only four years, and continues to improve their portfolio. Speakers will discuss incentives, strategies, priorities and certifications integrated into the design and planning process.

The purpose of this session is three-fold: To educate attendees about what embodied carbon is and how it's different from operational carbon. To discuss why reducing it is significant for global warming mitigation. And third, to describe the programs and policies local governments are considering to spur embodied carbon reduction. You will hear from experts about best practices to measure and reduce embodied carbon in common construction materials. You will learn how municipalities like Seattle and others are using these resources to implement internal and city-wide initiatives.

Join the growing community of radically responsible industry stewards using Hempcrete, a bio-composite material created from the woody core of the hemp plant combined with a lime-based binder. Trusted around the world as a robust, high-performance sustainable building system, HempLime entered the US market a decade ago and is poised to take the industry by storm. Delve into design and construction details and review the specifics of costs, source material supply, and obtaining building approval from officials.

Back in 2016, our team started a multiyear experiment, sponsored by Building America, on unvented roofs without spray foam or exterior rigid insulation, using an instrumented test hut with multiple test bays. The experiment examined cellulose vs. fiberglass insulation, interior vapor control membranes, diffusion vents at the ridge, interior humidification, inward vapor drive issues, and the effect of air barrier imperfections. Some preliminary results were presented at BuildingEnergy Boston in early 2018. After three winters of experimentation, this is the rest of the story.

Jurisdictions throughout the NESEA region and beyond are actively pursuing the decarbonization of new and existing buildings. Through legislation, executive action, and performance goals in the building code, the Northeast is leading the building industry toward zero carbon and zero energy buildings. In this session, particular focus will be on building a retrofit economy through technology deployment, zero energy policy development, energy benchmarking, performance reporting, and carbon reduction mandates.

Finch Cambridge is the largest new construction affordable housing development in the City of Cambridge in 40 years. As a Passive House project with a 105 kW PV array on the roof, it will also be one of the most operationally energy efficient buildings in Massachusetts. Currently in the final months of construction, this project has many important lessons to teach teams interested in Passive House certification. This session will focus on challenges, approaches tried, and how our extensive team of designers, builders and consultants worked together to execute.

Solar, energy efficiency, Passive House – these are the tools of the clean energy transition. But who are these tools for and who can afford them? Owners, developers, and residents of affordable housing in the Greater Boston region are asking these questions, identifying the barriers to accessing clean energy and the strategies for overcoming those barriers. Meanwhile, communities across the region are exploring ways to support this clean energy transition. How do we build partnerships across sectors to expand access and accelerate an equitable energy transition?

There’s been a surge in interest in Passive House multi-family new construction in the Northeast. So what kind of differences are we really talking about from conventional projects? Can we educate our design and engineering teams to get there? Hear from two of Massachusetts’ first Passive House affordable projects: Beacon Community’s 55-unit Old Colony and POAH’s 135-Unit Mattapan Station. Find out changes in design and construction both projects had to make. Learn about incremental costs and savings.

Maine Passive House (MPH) has used two different strategies in retrofitting existing homes. One strategy involves adding insulation to the outside of the building; the other strategy is to add insulation to the inside of the building. Most projects involve a mix of the two strategies. Along with added insulation and eliminating thermal bridging, MPH increases air tightness, installs high performing windows and doors, and adds mechanical ventilation systems in their projects.