The Building Science Podcast

Positive Energy
  • 4.7 (176)
  • DESIGN
  • UPDATED BIWEEKLY

The Building Science Podcast is a show hosted by MEP engineering firm Positive Energy principal Kristof Irwin. The show covers everything from the basics of building science to adjacent scientific disciplines to more fully understand how the built environment shapes our lives as human beings on planet earth.

  1. 5D AGO

    Our Hidden Roommates

    Kristof interviews Dr. Sarah Haines The Indoor Microbiome is the complex, invisible world of microorganisms living within our daily surroundings, serving as the primary ecological interface through which buildings influence human biology. In this light, we are beginning to view indoor environments not merely as passive shelters, but as powerful positive health interventions that can actively shape our immune development and long-term wellbeing. Today, we are joined by Dr. Sarah Haines, Assistant Professor at the University of Toronto and Principal Investigator of the IMEE Lab, to explore the foundational framework behind this shift. We will discuss the emerging perspective of "biologically informed architectural design" and the fact that architects and interior designers don’t just curate materials, they curate our basic microbial exposures and therefore our health and wellbeing. Sarah Haines Professor Sarah Haines’ interdisciplinary research integrates building science, engineering, and microbiology to analyze the impact the built environment has on human health. She uses cutting-edge microbiology techniques such as next-generation sequencing, metatranscriptomics, and bioinformatics to understand the impact of moisture on indoor environmental quality. Linking to climate change, her research explores the impact of weatherization and extreme weather events on indoor air quality, particularly in low income communities who may be at a higher risk for asthma. Her work aids in understanding indoor exposures from microorganisms and chemicals providing for a cleaner and sustainable indoor environment. Team Hosted by Kristof Irwin Edited by Nico Mignardi Produced by M. Walker

    1h 4m

  2. JAN 27

    Hydronics: The OG HVAC - Part 2

    Kristof interviews Benjamin Jewell. This is Part 2 of our latest series to familiarize our industry with the world of hydronics systems and air-to-water heat pumps. In Part 2 we’re rejoining the conversation to look at controls - the "central nervous systems" of these hydronics. We’re moving beyond old-school mechanical switches to a new class of microprocessor based systems that prioritize "outcomes"—like thermal comfort and air quality—rather than just reacting to thermostat calls. This shift is about adding intelligence that anticipates comfort needs and makes the system more stable and predictable for both the installer and the homeowner . We also dive into the high-stakes world of the global refrigerant transition and how hydronic systems allow a home to become "refrigerant agnostic" and truly future-proofed . We unpack the potential of natural refrigerants like R-290 (propane) and discuss why builders and developers are the key stakeholders in the transition of this product class from high-end homes to the baseline approach for every home that’s built. We wrap up by looking at how simplified "kit" solutions are finally removing the traditional barriers of labor and complexity to make hydronics accessible for the mainstream market. Benjamin Jewell Director of Carrier Hydronics NA (Climate Solutions Americas) As the Director of Carrier Hydronics North America within the Climate Solutions Americas division, Ben Jewell leads a multifaceted organization comprising Product, Engineering, and Technical Services teams. His leadership spans the entire product lifecycle, from initial development and long-term strategic planning to the integration of digital tools and portfolio management. Ben is dedicated to stewarding residential and light commercial hydronic products across a diverse range of differentiated brands, driving his team to win every day through innovation and operational excellence. Before joining Carrier, Ben spent over four years as a Senior Product Line Manager for Viessmann Climate Solutions. During this time, he managed extensive portfolios in the residential and light commercial sectors, specializing in heat pumps, chillers, domestic water heating, ventilation, indoor air quality, and air distribution. This deep technical foundation informs his current approach to solving complex climate challenges and delivering high-performance solutions to the market. Beyond his executive responsibilities, Ben is a passionate advocate for mentorship and industry education. He frequently invests his time in sharing resources and supporting those looking to solve tough problems that make the world a better place, including contributing to industry knowledge through podcasting. Driven by the goal of being a proactive force in the world, Ben aims to look back on his career with the confidence that he "happened to the world" by making a tangible, positive impact on the industry and the environment. On a personal level, Ben is a devoted husband and a father to three daughters, a dog owner, and a "food rescue" enthusiast. While he describes himself as an average fly fisherman and perhaps a naturalist in another life, he spends the bulk of his days enjoying what he considers his dream career. His journey has taken him from Iowa City to Milford, Connecticut, and Stony Brook, New York, eventually leading him to his forever home base in Fort Collins, Colorado. Despite his many moves, he remains a loyal Iowa Hawkeye at heart—Go Hawks! Team Hosted by Kristof Irwin Edited by Nico Mignardi Produced by M. Walker

    1h 22m

  3. JAN 20

    Buildings as Habitat: Biodiversity-Informed Investments in Public Health

    “First we shape our buildings, thereafter they shape us.”  - Winston Churchill (attributed) The natural world is humanity's original habitat. This habitat supports our physiological energy efficiency and is an important health intervention for the AEC industry. These are core perspectives that Helena van Vliet shares in this joint PHA-Building Science Podcast interview. Helena makes the clear case that we are “open systems” - we take in our environments, both physically and with our perceptions. Whether outdoors or indoors, our physical selves have their own experience of each environment we inhabit. This experience first informs our bodies, which have their own reactions of ease or dis-ease; and next, seemingly at the same time, this experience then informs our minds and our psychological reality comes to life. This interview is yet another beacon guiding us to deeply rethink how we deliver indoor spaces to ourselves. Enjoy the nourishing feast of ideas here! Helena van Vliet Helena van Vliet Dipl.-Ing. AIA is an internationally recognized expert in Biophilic Design. She is a registered Architect, Consultant, Researcher, Educator, and Speaker focusing on the direct connections between human and bio-habitat resilience in built environments. In her designs, consulting work and teaching, she integrates insights from her 40 years of practice, as well as data from her ongoing research in evolutionary biology, cognitive neuroscience, biopsychology, and chronobiology. Helenais the Principal at Helena van Vliet LLC, as well as a founding member of BioPhilly. Since 2013, she has served as a Steering Committee Member for the International Biophilic Cities Network. Since 2018, Helena has taught her interdisciplinary seminar “Environments for Well-Being” at Thomas Jefferson University, bringing together design and health science students to explore the building blocks - and underlying science - of spaces that support well-being. She is a frequent lecturer at the University of Pennsylvania, Drexel, Widener, the Bauhaus University Weimar, Germany, and the Politecnico di Milano, Italy. Ilka Cassidy Ilka Cassidy, Dipl.-Ing. Architecture, CPHC, is the co-founder of C2 Architecture and Holzraum System, with a deep passion for Passive House envelope design and building science. She focuses on the benefits of using natural building materials and specializes in offsite construction. With extensive experience in Passive House consulting and energy modeling, Ilka has a strong understanding of energy efficiency strategies. As a co-founder of C2 Architecture, she brought a sustainable design perspective to the firm from its inception. Through Holzraum System, she has worked to merge the precision and scalability of prefabrication with the use of healthy, low-carbon materials, all while optimizing energy efficiency with Passive House principles. Ilka is also committed to expanding knowledge in the industry, serving as co-host of the Passive House Accelerator Podcast and Construction Tech Live events. She is a frequent conference speaker and an active member of Green Building United in Philadelphia. She is a proud mom for her three girls and a visiting educator and McGill University.  Team Hosted by Kristof Irwin Edited by Nico Mignardi Produced by M. Walker

    1h 17m

  4. 12/23/2025

    Hydronics: The OG HVAC - Part 1

    In this episode we are once again diving into the world of hydronics systems and air-to-water heat pumps. These systems are poised to transform how we heat and cool homes and buildings in the US. In this Part 1 of a two part series, we’ll be tracing the historical "divergence" that pushed the US toward forced-air ducting while Europe stayed with the efficiency of water to move heat around inside buildings - remember that “moving heat” includes cooling. We discuss the basic components and function of hydronic systems in a guided component-level tour. We explain the potential to combine space heating and cooling with hot water production and the importance of simple components like buffer tanks that allow for load "decoupling"—the ability to store thermal energy and shift your home's energy loads to times when electricity is cheapest or the grid is less stressed. Benjamin Jewell Director of Carrier Hydronics NA (Climate Solutions Americas) As the Director of Carrier Hydronics North America within the Climate Solutions Americas division, Ben Jewell leads a multifaceted organization comprising Product, Engineering, and Technical Services teams. His leadership spans the entire product lifecycle, from initial development and long-term strategic planning to the integration of digital tools and portfolio management. Ben is dedicated to stewarding residential and light commercial hydronic products across a diverse range of differentiated brands, driving his team to win every day through innovation and operational excellence. Before joining Carrier, Ben spent over four years as a Senior Product Line Manager for Viessmann Climate Solutions. During this time, he managed extensive portfolios in the residential and light commercial sectors, specializing in heat pumps, chillers, domestic water heating, ventilation, indoor air quality, and air distribution. This deep technical foundation informs his current approach to solving complex climate challenges and delivering high-performance solutions to the market. Beyond his executive responsibilities, Ben is a passionate advocate for mentorship and industry education. He frequently invests his time in sharing resources and supporting those looking to solve tough problems that make the world a better place, including contributing to industry knowledge through podcasting. Driven by the goal of being a proactive force in the world, Ben aims to look back on his career with the confidence that he "happened to the world" by making a tangible, positive impact on the industry and the environment. On a personal level, Ben is a devoted husband and a father to three daughters, a dog owner, and a "food rescue" enthusiast. While he describes himself as an average fly fisherman and perhaps a naturalist in another life, he spends the bulk of his days enjoying what he considers his dream career. His journey has taken him from Iowa City to Milford, Connecticut, and Stony Brook, New York, eventually leading him to his forever home base in Fort Collins, Colorado. Despite his many moves, he remains a loyal Iowa Hawkeye at heart—Go Hawks! Team Hosted by Kristof Irwin Edited by Nico Mignardi Produced by M. Walker

    1h 24m

  5. 12/01/2025

    Beyond the View

    Windows are pivotal to the lived experience of a home. They impact the basic aesthetic and provide natural light, views, ventilation, and safety. However, they are also nearly always the largest single source of heat loss and gain - it's hard to overstate the importance of getting windows right, as they play a huge role in a building's energy use. Today, we're going to take a deep dive into high-performance architectural windows, exploring the technology that lets us control unwanted heat flow through conduction, convection, and radiation. We'll be looking at the technical specs U-factor, Solar Heat Gain Coefficient (SHGC), air leakage and visual transmittance, as well as the fundamental differences between US and European manufacturing philosophies. Article from Passive House Accelerator: How Windows Make (Or Break) Wall Performance Andrew Dryden Andrew Dryden is the Owner of Pivot Windows LLC. He is dedicated to promoting sustainable construction practices that enhance energy efficiency and overall building performance. His journey began during a transformative sabbatical year in the Pacific Northwest, where he constructed his own high-performance home. This hands-on experience ignited his passion for innovative building solutions and laid the foundation for Pivot Windows LLC. At Pivot Windows, Andrew is at the helm of several key projects aimed at increasing the accessibility of high-performance windows for residential and commercial clients. His strategic approach to program management ensures that each project is executed with precision, from initial concept to final installation. By fostering strategic partnerships within the industry, Andrew is able to source cutting-edge products that meet the evolving needs of the market while maintaining affordability for his clients. Team Hosted by Kristof Irwin Edited by Nico Mignardi Produced by M. Walker

    1h 31m

  6. 10/31/2025

    Cementing Carbon

    This is a crossover episode with the Spring Street Passive House education and advocacy series. Welcome to a pivotal conversation on the future of our built world. The concrete industry, indispensable for modern infrastructure, is facing an urgent mandate: reconcile its foundational role (pun) with its role as a source of environmental pollution. The scale of the emissions are staggering - if global concrete manufacturing were a country it would be the 3rd largest emitter, behind only China and the US (!). The good news is that with this a motivation the global concrete industry is now rethinking its entire lifecycle.  In this episode, host Kristof sits down with John Mead, one of the founders of Solid Carbon to talk about efforts to  transform concrete from a carbon emitter into a "net carbon sink. By converting waste carbon materials, wood being one, into a mass of solid carbon through pyrolysis and then using this carbon sink in a durable material through concrete we are making a huge impact in an industry that needs to make some powerful shifts in the years ahead. John Mead John Mead is an entrepreneur with 20 years leading companies focused on sustainable construction. He has a bachelor's degree in mechanical engineering from Oregon State University, and an MBA from George Fox University. He is CEO of Solid Carbon Inc., an Oregon company specializing in the commercialization of biochar-based ingredients for the ready mixed concrete industry. Solid Carbon's mission is to transform the concrete industry into a climate solution with climate smart concrete solutions to sequester carbon in the built environment. When not working on climate-friendly construction businesses he can be found coaching high school rugby, camping in the Cascades, gardening and admiring historic and modern architecture. Solid Carbon LinkedIn Team Hosted by Kristof Irwin Edited by Nico Mignardi Produced by M. Walker

    1h 1m

  7. 10/21/2025

    Systems Thinking to Save the World - 50 Years of Serious Commotion

    This may be the ultimate systems thinking interview. Beyond building science at the site scale, this is systems thinking to save the world.  Gail Vittori and Pliny Fisk III have their fingerprints all over the structural ideologies for ways of thinking that underlie what we now think of as the fields of sustainability, greenbuilding, indoor health and well-being and more.  Enjoy this thoughtful unpacking of ideas that span from systems thinking at the scale of the planet to human society to industry, products and materials. If you’re not familiar with Pliny Fisk III and Gaily Vittori, Max’s Pot, the Center for Maximum Potential Building Systems, or the Global Dreamlab, it’s about damn time that you are. Buckle up and enjoy this wild and fascinating ride with two of the brightest early lights in environmental sustainability  in the AEC and beyond. Pliny Fisk III Pliny Fisk III is a pivotal figure in the sustainability movement, whose career in architecture, landscape architecture, and the systems sciences spans more than four decades. He has dedicated his career to developing replicable prototypes, protocols, and policy initiatives that challenge conventional wisdom in building design, engineering, materials, and planning. His seminal life cycle-based protocols helped shape the first green building programs, and he collaborated on federal efforts like the Greening of the White House and the Greening of the Grand Canyon. He is also an inventor and the CEO and founder of two technology companies, Sustainable Earth Technologies and the EcoInventorium. Pliny’s influence extends into academia and policy, having held faculty positions at several major universities and served as an advisor to foundations like MacArthur and Gates. His policy initiatives include the Austin Green Building Program and the AIA’s Environmental Resource Guide, establishing new protocols with broad implementation. His impact has earned him numerous honors, including The Lewis Mumford Award and the U.S. Green Building Council’s Sacred Tree Award. Pliny has been recognized by Metropolis Magazine as a Visionary and by Texas Monthly as one of “35 People Who Will Shape Our Future.” Gail Vittori Gail Vittori  leads a life of discovery, of adventure, of collaborating with incredible people and finding opportunities to make a little bit of a movement of the needle on things that she is passionate about. Gail has been a key force in advancing green building policies, protocols, and prototypes at the local, state, and national levels, with a particular emphasis on the critical link between sustainable design and human health1. In 1989 she developed the initial conceptual framework for what would become the City of Austin’s Green Builder Program, recognized as the first green building program globally. Building on this foundational work, she went on to convene the Green Guide for Health Care in 2001, an initiative that catalyzed a revolution in the design, construction, and operations of healthcare facilities. Her expertise led her to serve as the Founding Chair of the LEED for Healthcare committee from 2004 to 2008, and she also co-authored Sustainable Healthcare Architecture. Gail has held several influential leadership positions in the sustainable building community. She served on the USGBC Board of Directors from 2002 to 2010, including a term as Board Chair in 20095. She also dedicated eight years to the Green Business Certification Inc. (GBCI) Board of Directors from 2011 to 2019, where she served as Board Chair from 2013 to 2019. Currently, she is the Vice-Chair of the Health Product Declaration Collaborative Board of Directors. Her vision and impact have earned her significant recognition, including the 2015 Hanley Award for Vision and Leadership and the 2020 USGBC’s Kate Hurst Leadership Award. Additionally, she was featured as an Innovator: Building a Greener World in TIME Magazine and was a Loeb Fellow at Harvard University’s Graduate School of Design. Team Hosted by Kristof Irwin Edited by Nico Mignardi Produced by M. Walker

    1h 25m

  8. 09/27/2025

    Navigating the Path to Passive

    This is a crossover episode with the Spring Street Passive House education and advocacy series. How do Passive House enclosure decisions actually happen? There’s a stubborn storyline that passive house designs go “too far” and result in a wholly different, and painful, design and construction process. The reality is that designing and building a Passive House is not all the different from building any project. In both cases you are working with a blend of the rigor of building science, the skill and craftsmanship of the construction team, the realities of project specifics like site, climate, budget, and schedule, and the personalities of the people involved. All of this then gets organized and systematized within the context of the Passive House standard of care which simply asks that we do all we can to ensure that a good design translates into long-lasting positive outcomes. Our guest today is Cameron Caja, CPHC. Hearing all he’s doing in the industry/world and the level of expertise he brings is an good reminder of the many intelligent caring people working tirelessly and with great resolve in the AEC today. Hearing his intelligence, wisdom and warmth is encouragement not lose sight of the goal of better buildings, and to not lose heart - we can do this. Links from the Episode: Spring Street Passive House Earth Advantage PHIUS PHI Cameron Caja Cameron Caja is the Business Development Manager at Positive Energy, a role that utilizes the skills he gained through diverse cultural landscapes and his passion for sustainable building practices. His story began as a builder's apprentice in high school, laying the foundation for a career marked by a deep appreciation for construction and design. Cameron studied at National Central University in Jhongli, Taiwan, and Soonchoonhyang University in South Korea, to understand how culture, language, and policy can guide development of the built environment. His studies continued in Japan, Thailand, and Russia, delving into the intersections of politics, housing, and food systems. Cameron earned his Masters degree in Education from the University of Arkansas, where he later managed specialized international education programs for the Graduate School. Sustainability, human and environmental health have always been at the heart of Cameron's endeavors. As a licensed residential builder and the owner of Polaris High Performance Homes, he committed that 100% of his projects would at least meet Energy Star, EPA Indoor airPlus, and WaterSense certifications. As one of the first Certified Passive House Consultants in the state of Arkansas, he actively contributes to advancing building standards in Kansas, Oklahoma, Arkansas, and Missouri as the Central Region Representative of the Phius Alliance Council. Cameron's commitment to community service is evident in his roles with the Habitat for Humanity of Washington County Construction Committee, Tri Cycle Farms Food Recovery Program, and the Omni Center for Peace, Justice, and Ecology. These organizations allow him to extend his impact beyond the realm of building science, addressing crucial social issues like homelessness and food insecurity. Team Hosted by Kristof Irwin Edited by Nico Mignardi Produced by M. Walker

    1h 8m
See All (157)

Trailer

4.7
out of 5
176 Ratings

About

The Building Science Podcast is a show hosted by MEP engineering firm Positive Energy principal Kristof Irwin. The show covers everything from the basics of building science to adjacent scientific disciplines to more fully understand how the built environment shapes our lives as human beings on planet earth.

Information

  • Creator
    Positive Energy
  • Years Active
    2015 - 2026
  • Episodes
    157
  • Rating
    Explicit
  • Copyright
    © Ecoscience, LLC, DBA Positive Energy
  • Show Website
    The Building Science Podcast

You Might Also Like