The Building Science Podcast

Could it be that Air-to-Water Heat Pumps (AWHP) using hydronic distribution are poised to become the new normal for residential HVAC systems? Can simply switching the thermal distribution fluid from refrigerant to water/glycol have significant positive impacts? As you will learn in this interview with Jim Bashford from SpacePak, the short answer to these questions may well be, simply, Yes. 

You don’t have to be a building nerd or an engineer for a question like this to be relevant and important to consider. There are many reasons why AWHP systems make an attractive alternative to our batch of current “normal” heat pumps that rely on refrigerant for thermal distribution. Some of the reasons AWHP are appealing include: (1) reduced refrigerant volumes, thus reduced refrigerant leakage into the atmosphere; (2) larger selection of indoor unit options relative to refrigerant based systems; (3) the ability to support comfort via thermally active surfaces (aka radiant heating/cooling); (4) your home is better future-proofed and more technology-agnostic, and (5) these systems affordably unlock thermal storage (for thermal loads), which can provide energy resilience for their owners as well as dispatchable grid-level energy storage This episode is why you listen to the Building Science Podcast, somehow this multifaceted emerging story has still not hit the mainstream. 

We spend the vast majority of our time inside yet we actually know very little about what it means to live indoors. This is the case even though what happens indoors impacts us in nearly every way. Our comfort, health and overall well-being all are deeply impacted by what's in the air we breathe and what’s happening in and on the surfaces all around us. 

Enter Corbett and Grace Lunsford. Knowing that what we don’t know about our homes matters a lot, they took on the challenge of creating a TV show on home performance for mainstream audiences. Their show, now in it’s third season makes it clear that a “good home” is far more than what it looks like and how much it will sell for in the market. In the process, Corbett and Grace have become leading voices in the role of educating us about the many and hidden dimensions of home performance. Join us in this episode as they unpack the why, the what, and they created the Home Diagnosis TV show on PBS.

Moving heat with a heat pump is an unsung superhero in the global energy transition. Chances are nearly 100% that you’re using a heat pump right now - to heat or cool yourself, refrigerate your food, or keep your car comfortable while you drive. The vapor compression process may be the thermodynamic engine of a heat pump, but where the rubber meets the road is the heat exchanger, aka “the coil”. 

Getting heat exchanger coils right is a balancing act. On one hand we want the coils wall material to be as thin as possible so they move heat efficiently, on the other hand we don’t want the working fluid, typically a high GWP refrigerant, to leak out into the sky. This is a costly hassle for us as well as a tragic outcome for the atmosphere. 

This is the backdrop for today’s conversation with Todd DeMonte on coils, coil failures, and the future of refrigerant based heat ex. Todd has been one of many smart folks around the world working to help society move past the vexing issue of formicary corrosion. Enjoy the feast of ideas in this episode!

As a society we are learning, slowly but surely, how to design and build healthy indoor spaces for ourselves and our loved ones. Seeing the need to both guide and accelerate this learning process, Paula Baker LaPorte and her wingman John Banta and Erica Elliot MD dedicated themselves to write a book. This happened 35 years ago with the 1st Edition of Prescriptions for a Healthy Homes, last year (in 2022) the 4th Edition was published and it is a richly updated treasure trove of motivation, guidance and actionable information that we all need to know more about. What we need now is a step change of sorts in the way society thinks about and delivers housing to itself. We need a Healthy Home Revolution.

With that in mind, Kristof sat down with Paula to have a conversation about her journey exploring and understanding the connection between the built environment and our health. After hearing her stories and absorbing the understanding and knowledge in her book, it is clear that homes can be so much more than we currently ask them to be. Homes are more than a visual-spatial-economic situation, more than a place to hold ourselves, our families and our stuff, more than an exercise in energy efficiency and resource use; The places we live are in truth highly immersive and tactile experiences for our bodies and minds, and profoundly impactful opportunities to promote our health and the health of the planet.

Designing and building a sustainable passive house is a powerful moment for all involved - the client, the architect, and the planet. For the owners the process is deeply personal and emotional, with layers of financial impacts and the significant time investment involved. For architects the key is to talk in a way that clients can hear them, and listen in a way that they can hear their clients*. For both the architect and the client the first few conversations set the stage for what comes next. 

“The pen controls the backhoe” is a slogan (from Part 1 of this series) that clearly expresses the power and deep impact of architecture on our world. Given that it is the architect’s pen that controls the backhoe, it makes sense to ask “What is it that controls the pen?” In this episode Corey Squire makes the case that it is the practices that each architecture firm employs that controls their pen. 

Stated another way: Why is it that some firms produce a consistent stream of high-performing buildings, while others have trouble crafting a single project that moves beyond traditional practice? The answer is Practice; the environment and practices within which each particular firm carries out or exercises its professional role in the society. Join us in this episode as Corey and Kristof enjoy a thoughtful and lively discussion of architectural practice along the dimensions of Vision, Culture, Process and Knowledge. This is one for all of you out there that recognize the power of architecture and want to better understand how to unleash its positive impact into the world. 

This two part interview on air filtration, air filters and filter media with Mark Davidson from Camfil covers a range of topics, from basic to advanced. Topics include the basics of particulate capture, the tradeoffs between filtration efficiency, clean air delivery rate, and energy use, filter media types, and electret degradation.  If you want to learn about the role of filtration in delivering clean indoor air for your self, or if your role in society has agency in making sure your clients are breathing healthy air, you will appreciate what you learn here. Mark is a filter nerd with the ability to break things down and communicate clearly.

This two part interview on air filtration, air filters and filter media with Mark Davidson from Camfil covers a range of topics, from basic to advanced. Topics include the basics of particulate capture, the tradeoffs between filtration efficiency, clean air delivery rate, and energy use, filter media types, and electret degradation.  If you want to learn about the role of filtration in delivering clean indoor air for your self, or if your role in society has agency in making sure your clients are breathing healthy air, you will appreciate what you learn here. Mark is a filter nerd with the ability to break things down and communicate clearly.

The 2020’s have so far been a decade of abundance and progress for society’s awareness and understanding of Indoor Air Quality (IAQ). Beyond and before the pandemic put IAQ on everyone's mind, researchers have been enjoying well funded support from various organizations, both public and private, to better understand the impacts of indoor air on our health and well being. Plus cutting edge technologies from novel mass spectrometers to real-time PCR and next-generation DNA sequencing are both expanding and accelerating our understanding of the richness, diversity and significance of indoor air quality in our lives. 

Join us for this engaging and somewhat nerdy discussion with Dr Pawel Misztal, an assistant professor from the University of Texas at Austin’s Civil Architectural and Environmental Engineering department. In this conversation Pawel unpacks the story of indoor air emissions and their impact on us. The emissions come from many sources including what we do, who we are (our bodies are highly active emission sources), and the microbes that live on every surface indoors.

There are few roles in society with the broad and lasting power of Architecture. Architecture both reflects and directs the story of a civilization and its cultural milieu by signaling what’s important, who has value, and how society functions. Recognition of the power of architecture in society sets the stage for today’s discussion with Corey Squire, a skilled sustainability consultant, a member of the AIA’s COTE Advisory Group, and an architectural optimist if there ever was one. Join us in this episode as Corey and Kristof start to digest the feast of ideas in Corey’s new book that will be coming out in the Fall of 2023.

The best place to generate electrical power is where it’s used. We all know that solar PV adds value for both owners and society by improving resilience, reducing energy costs and decreasing carbon emissions and climate impact. Yet traditional design practices and compressed schedules make it challenging for project teams to include integrated solar on their designs. 

The solution is Architectural Solar and the Architectural Solar Association knows that the key moves are early engagement and integration of architectural, structural and cladding systems. The time is now to consider solar as being architecturally significant and to realize that it does not always have to be relegated to the roof. The days of the Mr Potato HeadTM approach, where panels are stuck onto a home or building after they’re built, are over. Join us for forward-looking discussion with two industry experts in best practices for solar integration and design.

Is a building more like a river or a rock?

A building seems to just sit there*, so in that sense it seems to be more like a rock. But in reality every building material, and thus the entire building itself, is a snapshot in time of a river of resources and energy flowing from natural ecosystems into our use, and then, ultimately flowing back into the environment. 

All along the way, this flow of energy and resources emits carbon and other molecules into the sky, changing atmospheric chemistry and imbalancing our climate’s equilibrium. We’ve long known that this is both happening and that it’s a problem. What’s different now is that human society is waking up to the fact that we must work together to chart a new course forward. A course that recognizes the importance of reducing the both operational and embodied, or upfront, carbon emissions. 

That’s where our guest today comes in. Andrew Himes is all about helping groups move society forward by focusing on the convergence of technology, communication and social activism. Join us for this fast paced and compelling interview with Andrew as we talk about the theory of change for industry transformation using data & tools, policy change, and collective action.