Builders and developers, whether public or private, can learn from the success of Columbia County NY Habitat for Humanity, which uses Passive House methods to provide high-quality, healthy, and affordable housing. Key lessons include strategic site planning, envelope assemblies and details friendly to unskilled labor, and keeping to budget while coping with design changes, building code variations, fluctuating costs and availability of materials, and evolving Passive House standards.

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.

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.

What have we learned about the experience of living in a deep energy renovated home? Come hear 3 pioneers in the deep energy renovation space talk about what it was like to create and now live in a zero net energy (ZNE) renovated home. We've got data, we've got lessons learned, and we'll illuminate the human experience of living in a home that creates more energy than it uses on a net annual basis. The existing housing stock is where the vast majority of residential energy and carbon savings potential exists.

Today’s climate crisis requires us to bring innovation to every part of the construction process, including our use of existing building stock. Where older buildings can be retrofitted rather than replaced, we can reinvest embodied energy and drastically reduce first costs in building energy and carbon.

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.

Triple-decker homes, built in the late 19th and early 20th centuries to house immigrant workers, are an important New England housing resource. However, their energy performance is typically poor: they are often leaky, under-insulated, and heated with outdated fossil fuel systems. In this session, three organizations will describe scalable, replicable models to upgrade these iconic buildings. ABCD, which retrofits triple-deckers that house low-income individuals, will present on cost and energy savings achieved and challenges encountered.

This session will provide concrete tools and answers on how to draw down carbon in our buildings starting today. We’ll focus on low-rise buildings, where most new construction and renovations happen and which are currently under-represented in embodied-carbon design and analysis. We will present critical construction details such as band joist insulation selections and sloped ceiling retrofits, as well as whole-building design strategies.