Passive House Podcast

To register for our Reimagine Buildings: Best of Retrofit online conference on Friday, December 5, 2025, visit https://passivehouseaccelerator.com/ In episode thirteen of The Reimagine Edit series of the Passive House Podcast, host Zack Semke shares selected clips of insights from Al Mitchell, Kimberly Llewellyn, Greta Tjeltveit, Ya’el Santopinto, Wolfgang Feist, and Lisa White. This episode is split between two topics. The first addresses one of the most common questions veteran members of the high-performance building community hear from those who are new to the industry: How do you get your start? For some, that route may be through the trades. For others, it may be through design. There are also less orthodox pathways, particularly for folks with backgrounds in modeling, data management, or consulting. No matter what your background is, this episode provides some practical advice on beginning a career in high-performance building. The second topic is retrofits, particularly the new Phius REVIVE standard. Guests Lisa White and Al Mitchell, both of Phius, describe the basics of REVIVE and how resilience became the driving rationale behind the standard. The Reimagine Edit is a special series of the Passive House Podcast that shares curated insights from our Experts-In-Residence at the Reimagine Buildings Collective, our membership community of building professionals stepping up to tackle climate change. Learn more about the Reimagine Buildings Collective at https://www.reimaginebuildings.com

To register for our Reimagine Buildings: Best of Retrofit online conference on Friday, December 5, 2025, visit https://passivehouseaccelerator.com/ In this episode of The Passive House Podcast, Mary James interviews James Hartford and Juhee Lee Hartford of River Architects in Hudson Valley. The discussion covers the firm's focus on Passive House projects, mostly single-family homes with a mix of new constructions and retrofits. They touch on their first retrofit project affected by Hurricane Sandy, the evolving client interest in Passive House standards, and the firm’s growth from two to ten employees. They discuss the financial and practical challenges of Passive House projects, including material and energy considerations, involvement in advocacy through Passive House Hudson Valley, and the growing demand for such homes. They also highlight the benefits of prefab construction in difficult climates and the importance of builder experience. The episode concludes with a wishlist for products that could make achieving Passive House certifications more accessible.

In this episode of the Passive House Podcast co-host's Jay and Mary chat with Emily Mottram, founder of Mottram Architecture, about her architectural firm and her passion for building science and low-carbon residential architecture. Emily discusses her firm's focus on retrofits and new builds, explaining their approach to sustainable architecture using eco-friendly, bio-based materials. She shares insights on the complexity and importance of retrofitting existing structures, the challenges and benefits of panelized construction, and the holistic methods she employs to ensure the health and safety of building occupants. https://www.mottramarch.com/ Best of Retrofit: https://events.ringcentral.com/events/reimagine-buildings-retrofit/registration Thank you for listening to the Passive House Podcast! To learn more about Passive House and to stay abreast of our latest programming, visit passivehouseaccelerator.com. And please join us at one of our Passive House Accelerator LIVE! zoom gatherings on Wednesdays.

In this episode of The Passive House Podcast features hosts Mary James meets with Katie Schwamb, Managing Director at Building Energy Exchange (BE-Ex) to discuss emissions reduction and compliance with Local Law 97 in New York City. Local Law 97, sets carbon emissions limits for buildings over 25,000 square feet to help achieve near-zero emissions by 2050. Mary and Katie cover the importance of strategic planning, financial incentives, and challenges building owners face in complying with the law. Katie highlights Building Energy Exchange’s array of resources aimed at advancing energy-efficient, decarbonized buildings, including case studies, retrofit playbooks, and their Local Law 97 calculator. https://be-exchange.org/ Best of Retrofit: https://events.ringcentral.com/events/reimagine-buildings-retrofit/registration Thank you for listening to the Passive House Podcast! To learn more about Passive House and to stay abreast of our latest programming, visit passivehouseaccelerator.com. And please join us at one of our Passive House Accelerator LIVE! zoom gatherings on Wednesdays.

In this episode of The Passive House Podcast, host Jay Fox talks with Andrea Michael, an architect from Love Schack Architecture in Bozeman, Montana. They discuss Andrea's comprehensive home retrofit, aimed at improving energy efficiency and comfort. The retrofit included air sealing, adding insulation, installing a heat pump, ERVs, solar panels, and more. The conversation highlights Andrea's journey from initial DIY efforts to a full-scale renovation, revealing significant energy savings and improved indoor air quality. The episode also touches on the challenges and successes of integrating sustainable building practices in Montana. https://loveschackarchitecture.com/ See Andrea December 5th at Best of Retrofit: https://events.ringcentral.com/events/reimagine-buildings-retrofit/registration Thank you for listening to the Passive House Podcast! To learn more about Passive House and to stay abreast of our latest programming, visit passivehouseaccelerator.com. And please join us at one of our Passive House Accelerator LIVE! zoom gatherings on Wednesdays.

In the twelfth episode of The Reimagine Edit series of the Passive House Podcast, host Zack Semke shares selected clips of insights from Jake Bruton, Ben Bogie, Michael Ingui, Ed May, Kristof Irwin, and Ashley Wisse. This episode explores how practitioners across the Reimagine Buildings Collective are evolving the language and practice of high-performance building—shifting the focus toward health, comfort, and durability; tackling the realities of partial retrofits; leveraging modeling for better design decisions; and exploring radiant cooling and geothermal systems. Together, they offer a grounded perspective on how builders and designers can communicate value, raise standards, and accelerate the movement toward better buildings for all. The Reimagine Edit is a special series of the Passive House Podcast that shares curated insights from our Experts-In-Residence at the Reimagine Buildings Collective, our membership community of building professionals stepping up to tackle climate change. Learn more about the Reimagine Buildings Collective at https://www.reimaginebuildings.com

In this episode of The Passive House Podcast, host Mary James speaks with Kara Haggerty Wilson, Design Director at Onion Flats. Kara discusses the company's focus on scaling up deep energy retrofits. She highlights their journey from initial projects in Pennsylvania to more extensive work in Massachusetts, including the challenges and successes of projects like the 130-year-old Hano Homes retrofit. Kara shares insights on navigating site-built versus panelized solutions, the importance of detailed building scans, and the evolving interest in deep energy retrofits among developers. The conversation also touches on technological advancements and the complexities of integrating new systems into old structures. https://www.onionflats.com/ https://passivehouseaccelerator.com/events/101-deep-energy-exterior-retrofits?date=2025-11-05

This week on the Passive House Podcast we welcome Ben Walsham, the founder and director of ARKATA, based in Brunswick, Victoria. Trained in architecture and now a registered NatHERS Accredited Energy Efficiency Assessor, Ben empowers architects—as well as homeowners, builders, and developers—across Australia to create homes that are not only energy‑efficient, but comfortable, healthy, and resilient With a background in residential architecture and on-site building, Ben witnessed first-hand the pressing need for better performance in homes. This inspired his transition into sustainability consulting and ultimately to launching ARKATA in 2023. ARKATA’s mission reflects Ben's philosophy: “Uncover the power of sustainability” through a human‑centered lens, where efficiency measures translate into tangible comfort and wellbeing for occupants. https://www.linkedin.com/in/ben-walsham-104188148/ https://linktr.ee/arkata.au

In this episode of the Passive House Podcast, Ilka Cassidy and Kristof Irwin are at PhiusCon 2025, highlighting key sessions and interviews with industry experts. The conference explored a variety of themes including performance, purpose, and the power of community in the Passive House movement. Key takeaways included insights on air tightness, ventilation, innovative financing models, and the challenges and successes in scaling up Passive House projects. https://www.phius.org/phiuscon Thank you to Ikon Windows for sponsoring this episode of the Passive House Podcast! https://www.ikonwindows.com/ Thanks to Jennie Eber, Tom Bassett-Dilley, Kai Fast, Sayo Okada, Beth Campbell, Beverly Craig, Kazumasa Tsushima, Daiji Sato, and Alexander Gard-Murray for joining us! Thank you for listening to the Passive House Podcast! To learn more about Passive House and to stay abreast of our latest programming, visit passivehouseaccelerator.com. And please join us at one of our Passive House Accelerator LIVE! zoom gatherings on Wednesdays.

In this episode of the Passive House Podcast, Matthew Cutler Welsh talks with Matthew Crucifix, Director of Development at Stonewater, they discusses the organization's efforts in providing affordable and sustainable housing in the UK. Crucifix outlines Stonewater's expansive reach, managing around 40,000 homes, and their current focus on retrofitting existing homes to improve energy efficiency. Highlighting the financial challenges and solutions, including government grants and their in-house subsidy pot. He also delves into the specifics of their Passive House projects, like Cherry Grove, emphasizing the goal of building homes that are affordable, energy-efficient, and environmentally friendly. The conversation concludes with insights into the future of housing in the UK, stressing the importance of sustainable construction methods and energy resilience. https://www.stonewater.org/ Thank you for listening to the Passive House Podcast! To learn more about Passive House and to stay abreast of our latest programming, visit passivehouseaccelerator.com. And please join us at one of our Passive House Accelerator LIVE! zoom gatherings on Wednesdays.

In this episode of the Passive House Podcast, Mary James and Ilka Cassidy interview Tony Lisanti, managing director at Integral Building and Design and QA/QC Manager for Phius. The discussion delves into various rating systems for high performance and passive houses, focusing on the HERS rating method, its standards, and applications. Tony explains his extensive experience in the energy and engineering fields and how he provides certification services for numerous federal and state programs. He further details the process of becoming a HERS and Phius rater, emphasizing the importance of early engagement in the project, thorough QA protocols, and consistent communication between designers and raters. The episode also highlights case studies, including a modular senior housing project and a panelized straw system, illustrating the complexities and benefits of these high-performance building standards. https://www.phius.org/ https://integralbuilding.com/ https://collective.reimaginebuildings.com/ Thank you for listening to the Passive House Podcast! To learn more about Passive House and to stay abreast of our latest programming, visit passivehouseaccelerator.com. And please join us at one of our Passive House Accelerator LIVE! zoom gatherings on Wednesdays.

In the eleventh episode of The Reimagine Edit host Zack Semke strings together some pearls of wisdom from leading Passive House experts across three continents and include Martín Comas, Ed Ettinger, Lindsey Love, Joe Lstiburek, Tomas O’Leary, and Shefali Sanghvi. Each gem is selected from a conversation that took place inside the Reimagine Buildings Collective, either during one of the Reimagine Tuesday interviews or a Friday AMA. Speakers explore how to encourage clients to pursue Passive House certification, how to better condition and dehumidify hot and moist climates, ways to improve kitchen ventilation, some tips for using natural materials, and more! The Reimagine Edit is a special series of the Passive House Podcast that shares curated insights from our Experts-In-Residence at the Reimagine Buildings Collective, our membership community of building professionals stepping up to tackle climate change. Learn more about the Reimagine Buildings Collective at https://www.reimaginebuildings.com

In this episode of The Passive House Podcast, join Jay Fox and Mary James as they dive deep into sustainable building systems with Greta Tjeltveit, a Building Science Consultant at 4EA Building Science and Board President of Passive House Northwest. Greta shares her inspiring journey from researching post-Katrina rebuilding efforts in high school to her current role, discussing her experiences and insights into the evolving fields of green building, building science, and Passive House design. They also explore topics such as the importance of early testing in Passive House projects, challenges of ventilation systems in the Pacific Northwest, and the impacts of wildfire smoke on indoor air quality. Don't miss this engaging discussion on the latest trends and innovations in sustainable architecture and Passive House certification. Join Greta this Wednesday: https://passivehouseaccelerator.com/events/101-balanced-ventialtion?date=2025-10-01 https://collective.reimaginebuildings.com/ Thank you for listening to the Passive House Podcast! To learn more about Passive House and to stay abreast of our latest programming, visit passivehouseaccelerator.com. And please join us at one of our Passive House Accelerator LIVE! zoom gatherings on Wednesdays.

In this episode of The Passive House Podcast, join Ilka and Jay for their in-depth discussion with the members of the Reimagine Buildings Collective's innovative Summer Labs. The episode showcases the experiences and insights of various industry professionals who participated in these member-led groups. Featuring Paul Heron, Randall Anway, Lauren Shadid, Valerie Amor, Sandra Lester, Fabrizio Maso, Buck Moorehead, Lloyd Alter, Mark Attard, Rainger Pinney, and Mike Fowler. https://collective.reimaginebuildings.com/ Thank you for listening to the Passive House Podcast! To learn more about Passive House and to stay abreast of our latest programming, visit passivehouseaccelerator.com. And please join us at one of our Passive House Accelerator LIVE! zoom gatherings on Wednesdays.

In this episode of The Passive House Podcast, Mary James interviews Az Rashid Head of Design at Barratt London. Az shares details about Barratt London's focus on large-scale, mixed-use, residential-led regeneration projects within London, and their collaboration with Transport for London (TfL) to develop properties near transit lines. He discusses his journey from architecture to his current role and explains Barratt London's recent commitment to building all new homes to Passive House standards, including the anticipated benefits for residents and the environment. The episode covers their methodical approach to training, research, and development to achieve Passive House certification, as well as their plans to begin delivering Passive House homes by 2029. https://www.barratthomes.co.uk/new-homes/london/ Reimagine Building Massive Impact (Sept 19): https://events.ringcentral.com/events/reimagine-buildings-massive-passive/registration https://ukphc.org.uk/ Thank you for listening to the Passive House Podcast! To learn more about Passive House and to stay abreast of our latest programming, visit passivehouseaccelerator.com. And please join us at one of our Passive House Accelerator LIVE! zoom gatherings on Wednesdays.

In this episode of the Passive House Accelerator Podcast, Ilka Cassidy and Mary James are joined by sustainability experts Amy Cornelius, Paul Thompson, and Joe Messier as they delve into a groundbreaking retrofit project in Philadelphia. This six-part demonstration series, hosted by Green Building United, examines a project aligning with the new Phiuss REVIVE standard and the Living Building Challenge core principles. Listen as they discuss the integration of these standards, the challenges of retrofitting row homes, and the educational impact of their collaborative series. Discover key takeaways, innovative approaches to sustainability, and the surprising synergies between these certification programs. Tune in for an insightful exploration of how theory meets practice in sustainable building retrofits.

In this episode of the Passive House Podcast, co-hosts Jay Fox and Mary James speak with Gaelen McKee, Founder of Brooklyn Solar Works. They dive in to the company's origins, current projects, including work with co-ops and commercial buildings, and their plans for expanding into ground-mounted solar installations. Galen also touches on the impacts of tariffs, permits for residential batteries, and the future of whole-home electrification in New York City. https://brooklynsolarworks.com/ Thank you for listening to the Passive House Podcast! To learn more about Passive House and to stay abreast of our latest programming, visit passivehouseaccelerator.com. And please join us at one of our Passive House Accelerator LIVE! zoom gatherings on Wednesdays.

In this episode of the Passive House Podcast, Matthew Cutler Welsh interviews Jessica, a high-performance building consultant at Climate Shore in Adelaide. They discuss Jessica's transition from energy efficiency compliance to specializing in high-performance building with a focus on mitigating moisture risks. Jessica emphasizes the importance of proper construction practices and ventilation in preventing mold, touching on the challenges of getting builders and homeowners to adopt better practices. She highlights the relevance of Passive House standards and her involvement in promoting building science in Australia. Jessica is also the founder and co-host of the Build Insite podcast, where she explores building science, performance-based design, and practical strategies to deliver healthier, more efficient homes. Her expertise encompasses blower door testing, NHERS compliance, condensation risk modelling, and navigating NCC‑2022 regulations—all aimed at improving standards in residential and commercial construction. https://www.linkedin.com/in/jessica-allen-esd/ https://www.climasure.com.au/ https://www.endurobuilders.com.au/ https://building-sciology-poddie.podcastpage.io/?v=lfcm https://www.instagram.com/building.sciology/ https://www.instagram.com/building.sciology/ https://www.tiktok.com/@building.sociology Thank you for listening to the Passive House Podcast! To learn more about Passive House and to stay abreast of our latest programming, visit passivehouseaccelerator.com. And please join us at one of our Passive House Accelerator LIVE! zoom gatherings on Wednesdays.

In this episode of the Passive Hosue Podcast, Zack Semke welcomes Michael Quast, the new CEO of Passive House Canada. Michael shares his diverse background in construction, business development, and media, emphasizing his passion for sustainable building. They discuss Michael's journey to Passive House Canada, his experience with straw bale construction, and his focus on fostering collaboration and breaking down silos within the sustainability sector. This episode highlights the importance of engaging both the building community and consumers to promote high-performance, energy-efficient buildings. https://www.passivehousecanada.com/ Thank you for listening to the Passive House Podcast! To learn more about Passive House and to stay abreast of our latest programming, visit passivehouseaccelerator.com. And please join us at one of our Passive House Accelerator LIVE! zoom gatherings on Wednesdays. https://passivehouseaccelerator.com/articles/passive-house-helping-shape-state-energy-codes https://passivehouseaccelerator.com/podcast/passive-house-podcast-ep-36-robyn-wark-bc-hydro https://passivehouseaccelerator.com/podcast/passive-house-podcast-encore-ep-robyn-wark-bc-hydro

In this episode of The Passive House Podcast, Mary James interviews Stephen O'Shea, head of Sustainable Construction at Carin Homes. Steven discusses the company's focus on large-scale residential projects, their commitment to Passive House standards, and the significant benefits for residents. He shares his journey from architecture to sustainable design, training strategies for implementing these standards, and the ecological measures taken on building sites. The episode also covers the need for public education on Passive House and previews an upcoming conference in collaboration with the Passive House Trust. https://www.cairnhomes.com/ Thank you for listening to the Passive House Podcast! To learn more about Passive House and to stay abreast of our latest programming, visit passivehouseaccelerator.com. And please join us at one of our Passive House Accelerator LIVE! zoom gatherings on Wednesdays.