Trends and Hot Topics The Shifting Energy Code Landscape in Massachusetts

Specialized Opt-In Commercial and Multi-Family Residential Minimum Requirements

Passive House is a code compliant option for ALL building types.

By Andrew Steingiser

Architects must address many factors when designing a building. Just to name a few, there’s zoning, context, historical considerations, massing, program, accessibility, client needs, and cost. Let’s not forget conveying meaning through the design that acknowledges the canons of architectural theory and precedent – the interesting part. Then add the following to the mix: designing to address the climate crisis and keeping up with the shifting code landscape. That’s a lot to consider!

Architects who work in Massachusetts should be aware of recent changes to the Energy Code released in December 2022 by the Massachusetts Department of Energy Resources (DOER). As part of the updated 10th edition of the Massachusetts Building Code, the new base Energy Code includes updates to the Stretch Energy Code as well as the addition of a second, more advanced tier of the Stretch Energy Code known as the Specialized Opt-In Stretch Code

Architects who work in Massachusetts should be aware of recent changes to the Energy Code released in December 2022 by the Massachusetts Department of Energy Resources (DOER). As part of the updated 10th edition of the Massachusetts Building Code, the new base Energy Code includes updates to the Stretch Energy Code as well as the addition of a second, more advanced tier of the Stretch Energy Code known as the Specialized Opt-In Stretch Code. These code changes are based on the 2021 International Energy Conservation Code with Amendments. The 299 out of 351 municipalities in Massachusetts already enrolled in the previous Stretch Energy Code will continue to follow the updated Stretch Energy Code. Towns that vote to adopt the new Specialized Opt-In Stretch Code will be held to the requirements of that code. The implementation of the more stringent requirements in both stretch codes will advance progress toward the Commonwealth’s 2030 and 2050 carbon emissions reduction mandates.

You should be aware of a few key changes in the updated Energy Code. First, the Stretch Code and the Specialized Opt-In Code include multiple new paths based on the size and program of your building. You will have to check the code to determine which compliance path your building falls under. Depending on the applicable path for your building, you may have more than one option for code compliance. The path you select will set the performance targets that your building is required to achieve. Passive House remains a code compliance option for all building types.

The new Stretch Code and Specialized Opt-In Code apply to all buildings of all sizes, including additions and alterations. Most paths will require energy modeling. For many commercial and multifamily residential buildings, the energy modeling process will determine the R-value and U-value requirements for the building enclosure.

The code updates include a simplifed enclosure backstop calculation. The performance requirements resulting from the modeling for your selected path will likely exceed the minimum requirements of the backstop calculation and will determine your building’s enclosure requirements. There is also now a requirement for all-electric heating systems if you want to design an all-glass building. The energy modeling process will likely show that all-glass is not going to be feasible anymore for most buildings. Sorry, my fellow black-spectacled friends!

The code updates place a greater emphasis on energy demand reduction measures, something that those of us in the Passive House community are well familiar with. A high-quality, airtight building enclosure with continuous control layers and the elimination of thermal bridging will allow for passive reduction of energy use in heating and cooling systems. Airtightness testing is now required to confrm the performance of air barriers in the building.

All these changes in the Energy Code are creating a shift in the traditional design process. Projects will beneft from an early-phase integrated design approach, where design teams think a little bit about everything starting on day one. Energy modeled performance requirements will help inform and shape your designs from an early phase and will continue to confrm the ongoing performance compliance through the design process. You’ll need to pay careful attention to building enclosure detailing and mechanical system specifcations earlier in the design process than you are used to.

While this may seem like a lot to take on, these new code requirements will start us down a path toward future-proofng our buildings. The upcoming penalties from programs like BERDO represent the closest thing we have in the U.S. to a carbon tax and will only continue to gain prominence. Also, what is the expected life span of our buildings? What future climates will our buildings need to shelter us from? By acting now, we can avoid the levies of the future.