The code does this through increased envelope performance and energy recovery ventilation partnered with highly efficient space heating. The former being key to making the heating and cooling system perform most efficiently. Any community may choose to adopt the more stringent Specialized Opt-in Code which requires all-electric net zero buildings. The Opt-in requires town approval, but we may see the first community with this code by the end of 2023. 

I’m excited by the breadth of net zero projects Arrowstreet has seen in almost a decade since our first net zero project. Today we’re designing almost 3 million square feet of net zero buildings. These projects are large and small, offices, schools, multifamily, and life science facilities. A report by Built Environment Plus released in 2021 indicated over 7 million square feet of net zero and net zero ready buildings in Massachusetts; the “ready” part being a building that meets the low energy side of the equation but hasn’t procured renewables for energy used. The updated report to be released soon will probably show at least double the 2021 amount.   

Arrowstreet in association with Adrian Smith + Gordan Gill began working with Midwood Investment and Development in 2018 on the first net zero office high-rise in Boston. This project, 11-21 Bromfield Street, sought to rewrite the norm expected of a high-rise building by using low glazing ratio and all-electric heat pump systems. Five years later, the new Stretch Code is codifying that norm. In addition, Arrowstreet is working on over 1 million SF of net zero life science facilities. Life Science facilities are especially important examples because of their higher energy intensity as well as exponential growth of development in greater Boston. Don’t get me wrong the new code brings with it bigger changes, and more detailed analysis, than in previous stretch code updates, however, the good news is that projects have been proving the economics and technical challenges for over a decade in Massachusetts.   

While the updated Stretch Code now covers additions and alterations, it still leaves a large gap in bringing existing building stock up to the level of efficiency needed. It is important to keep existing buildings, rather than demolish them, for many reasons including avoiding embodied carbon emitted by new construction. The industry needs to find creative solutions to tackle existing buildings while keeping these assets financially viable. That is how Arrowstreet approaches existing buildings, but it does add a layer of complexity and analysis. Arrowstreet helps building owners, or those looking for new spaces, understand the carbon emissions and renewable impacts of decisions until 2050 while exploring additional funding available for meeting higher performing solutions. 

Kate Bubriski is a Principal and Director of Sustainability & Building Performance at Arrowstreet Architecture and Design.