E6: Zero Energy Buildings – The Equation is Easier Than You Think!

Mainstream demand for highly efficient, resilient, and cost-effective buildings is greater than ever before. More people are looking to integrate zero energy design and construction strategies without having to sacrifice modern conveniences and amenities. So, how do we implement solutions that enable us to use less energy… without feeling like we’re using less energy?

To answer this question, we sit down with SWA sustainability experts, Paula Zimin and Karla Butterfield, to discuss what it means to achieve zero energy status and learn how we can accomplish this among various building typologies and sectors. Join us for this exciting and in-depth look at zero energy buildings! 

Episode Guests: Paula Zimin & Karla Butterfield

Paula ZiminPaula Zimin is the Director of Sustainable Building Services at Steven Winter Associates (SWA). She specializes in professional architecture and design, with particular expertise in high performance design within the commercial and residential sectors.
Karla Butterfield HeadshotKarla Butterfield is a Sustainability Director at SWA, working with residential buildings. She has 25 years of experience, with expertise in sustainable consulting services, program certification support, and implementation of high performance building technologies.

Zero Energy Information and Resources


SWA Resources & Net-Zero Projects:

Clarification: When Paula discusses the total source energy consumption of a building, she uses the number 38. This refers to 38 KBTUs (or 30,000 BTUs) per square foot, per year. This pertains to source energy, not site energy, and is also known as “primary energy” in Passive House. Although they are considered the same in Passive House, source energy and primary energy have subtle differences according to the EPA.

Correction: Karla mentioned a HERS 45 was a requirement for DOE’s ZERH program. This is not strictly true; the HERS target varies somewhat with climate and home size. A very large home in the Northeast might need to get a HERS index of 40 to comply, whereas a small home might need a HERS index of 52.

Upcoming Events and Conferences

BuildingEnergy NYC, October 3-4

The BuildingEnergy NYC Conference + Trade Show is NYC’s premier event for professionals and practitioners in the fields of high-performance building, energy efficiency, and renewable energy. SWA will have various speakers presenting on an array of building energy topics. Come visit us! 

NAPHN Conference, October 17-21

Join North America’s Passive House community as it convenes in a surprising hotspot of Passive House design and construction: Pittsburgh, Pennsylvania. SWA has four sessions at the NAPHN conference on a variety of Passive House topics. Hope to see you there!

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About Buildings and Beyond

Buildings and Beyond is a production of Steven Winter Associates. We provide energy, green building, and accessibility consulting services to improve the built environment. For more information, visit


Robb Aldrich | Kelly Westby

Production Team

Heather Breslin | Alex Mirabile | Dylan Martello

Next up on Buildings and Beyond…

Improving the Efficiency of Your Single-Family Home

Guest: Srikanth Puttagunta

Srikanth Puttagunta Headshot