The Secret Life Of Concrete by Positive Energy

Concrete is everywhere. We all see it every day but what do we really know about concrete? This seemingly simple material is any but simple. Listen and learn about the past, present and future of this evolving technology. Prepare to have your mind blown in this episode of the show as we explore the incredible history and composition of concrete with Matt Carlton and Lee Lawrence of WJE. You'll never see concrete the same way again.

Our Guests


Lee Lawrence

Principal, Director of Practice Development, and South Region Director at WJE.


Matt Carlton

Principal & Unit Manager at WJE.

Notes From The Episode


(/riːˈɒlədʒi/; from Greek ῥέω rhéō, "flow" and -λoγία, -logia, "study of") is the study of the flow of matter, primarily in a liquid state, but also as "soft solids" or solids under conditions in which they respond with plastic flow rather than deforming elastically in response to an applied force. It is a branch of physics which deals with the deformation and flow of materials, both solids and liquids.

Flying buttress

(arc-boutant, arch buttress) a specific form of buttress composed of an arched structure that extends from the upper portion of a wall to a pier of great mass, in order to convey to the ground the lateral forces that push a wall outwards, which are forces that arise from vaulted ceilings of stone and from wind-loading on roofs.

The defining, functional characteristic of a flying buttress is that it is not in contact with the wall it supports, like a traditional buttress, and so transmits the lateral forces across the span of intervening space between the wall and the pier. To provide lateral support, flying-buttress systems are composed of two parts: (i) a massive pier, a vertical block of masonry situated away from the building wall, and (ii) an arch that bridges the span between the pier and the wall — either a segmental arch or a quadrant arch — the flyer of the flying buttress.

The Pantheon (Was Built Out Of Concrete)

The building is circular with a portico of large granite Corinthian columns (eight in the first rank and two groups of four behind) under a pediment. A rectangular vestibule links the porch to the rotunda, which is under a coffered concrete dome, with a central opening (oculus) to the sky. Almost two thousand years after it was built, the Pantheon's dome is still the world's largest unreinforced concrete dome. The height to the oculus and the diameter of the interior circle are the same, 142 feet (43 m).

Portland Cement

Portland cement is the most common type of cement in general use around the world as a basic ingredient of concretemortarstucco, and non-specialty grout. It was developed from other types of hydraulic lime in England in the mid 19th century, and usually originates from limestone. It is a fine powder, produced by heating limestone and clay minerals in a kiln to form clinkergrinding the clinker, and adding 2 to 3 percent of gypsum.[clarification needed] Several types of Portland cement are available. The most common, called ordinary Portland cement (OPC), is grey in colour, but white Portland cement is also available. Its name is derived from its similarity to Portland stone which was quarried on the Isle of Portland in Dorset, England. It was named by Joseph Aspdin who obtained a patent for it in 1824. However, his son William Aspdin is regarded as the inventor of "modern" Portland cement due to his developments in the 1840s.[1]

Concrete Petrography

Petrography is a branch of petrology that focuses on detailed descriptions of rocks. Someone who studies petrography is called a petrographer. The mineral content and the textural relationships within the rock are described in detail. The classification of rocks is based on the information acquired during the petrographic analysis. Petrographic descriptions start with the field notes at the outcrop and include macroscopic description of hand specimens. However, the most important tool for the petrographer is the petrographic microscope. The detailed analysis of minerals by optical mineralogy in thin section and the micro-texture and structure are critical to understanding the origin of the rock. Electron microprobe analysis of individual grains as well as whole rock chemical analysis by atomic absorption, X-ray fluorescence, and laser-induced breakdown spectroscopy are used in a modern petrographic lab. Individual mineral grains from a rock sample may also be analyzed by X-ray diffraction when optical means are insufficient. Analysis of microscopic fluid inclusions within mineral grains with a heating stage on a petrographic microscope provides clues to the temperature and pressure conditions existent during the mineral formation.

Board Form Concrete


Event - Not Your Father’s Concrete!: A breakfast seminar and networking opportunity

Join WJE for a presentation and discussion of the perils of ready-mix concrete and the state of practice. We will also discuss self-consolidating concrete, the advantages and disadvantages as well as new-age additives and what works best when.

This program will qualify for AIA/AICP Continuing Education Credits.


Special thanks to The Humid Climate Conference for their generous support.

Design & Construction In Humid Climates by Positive Energy

Yes. We're going to have a chat about humidity. If you live in a heating dominated, dry climate you might be thinking "what good is this for me to hear?" and I wouldn't blame you. But frankly, the more we know about humidity, the better we can understand how things work without it too. So dig in and think about how moisture affects the things we design and build. In this episode of The Building Science Podcast, we’ll explore the potential upside and downside of designing and building in humid climates.

If you're serious about building high performance homes in humid climates, you don't want to miss this year's Humid Climate Conference in Austin. Tickets are on sale now and we at The Building Science Podcast are thrilled to sponsor this year's conference. Don't miss it! The Humid Climate Conference is organized entirely by volunteers from the PHAUS (Passive House) Chapter in Austin with support from the national organization, PHIUS


What Is A Climate Zone?

DOE climate zone map.preview.jpg
One of the fundamental principles of building science is that buildings must be suited to their climate. When they’re not, problems can ensue. Maybe it’s just that they’re not as efficient as they should be. Maybe it’s worse. Put plastic between the drywall and framing of your exterior walls in Ottawa, and it can help control vapor drive from the interior air and its associated moisture problems (rare in all but except in extremely cold climates). Put that plastic in the same place in Georgia, and you’re going to rot the walls.

The first thing to know about climate zones is that we divide them up based on two parameters: temperature and moisture. The map at the top of this article, from Building Science Corporation, is one that seems to be in a lot of the curricula for home energy rater and other energy auditor classes. The fancy word for this type of division is hygrothermal, and Building Science Corp. has a nice interactive map of hygrothermal regions.

The map above divides all of North America into broad regions based on temperature and then humidity. The International Code Council has a more fine-grained approach to climate zones,† as shown below in the map of the US from the International Energy Conservation Code (IECC). Each zone has a number, starting with 1 for the hottest US climate, the southernmost tip of Florida, and going up to 8, the coldest parts in Alaska.
— Dr. Allison Bailes, III

Aridity & Humidity: Where & Why? 


Special thanks to Panasonic for their generous support. 


Don't Wait For The Market by Positive Energy

In our first episode of season 4, Kristof interviews James Geppner of Erase40 and Big Yellow Cab on the topic of behavioral change and market transformation. Building Science stands poised to change the way we deliver conditioned space to society. There are many angles by which we can dissect exactly how to do that. In this episode, we're going to explore how YOU can change the market.


James Geppner

James has advised and developed initiatives for nonprofits, new ventures and mature companies in infrastructure, technology, media, education, health and housing. Following his years in Project Finance, where he evaluated companies and studied markets, he has applied social science (and competitive theory) to a range of issues in order to see what’s shaping a market, a cause or a behavior.

He founded Big Yellow Cab in order to apply social science research and the procedures of behavior change to important social and environmental issues. He has advised nonprofits, new ventures and global companies. Most recently he did an extensive analysis of the market for passive buildings and the decision-making process of buyers, funders and end users in order to find clues as to how to increase the size of the market and how to reduce the barriers to widespread adoption of passive technology. He founded Erase40 in order to develop market based initiatives that drive up demand for passive buildings and in order to serve as a decision lab for different players in the building ecosystem. He is a graduate of NYU and of SGIB’s investment banking program. 


Big Yellow Cab
Freakanomics Radio Episode (Mentioned) 

Special thanks to Panasonic for their generous support.



The BeautyOf Hot Water by Positive Energy

Live from the Texas Society of Architects 2017 Expo and Convention, we're proud to bring you a series of episodes exploring "the multiple dimensions of beauty" through interviews with some phenomenal architects, builders, and consultants. 

In this episode we interview water engineering expert, Gary Klein of Gary Klein & Associates.

Gary Klein

Gary Klein, President of Gary Klein & Associates has been intimately involved in energy efficiency and renewable energy since 1974. One fifth of his career was spent in the Kingdom of Lesotho, the rest in the United States. Mr. Klein has a passion for hot water: getting into it, getting out of it and efficiently delivering it to meet customers' needs. 

After serving 19 years with the California Energy Commission, he has provided consulting on sustainability since 2008. Mr. Klein received a BA from Cornell University in 1975 with an Independent Major in Technology and Society with an emphasis on energy conservation and renewable energy.

Special thanks to Bautex Systems for their generous support of our live recorded episodes at the 2017 TxA Expo & Convention. Be sure to stop by their website, learn about their innovative product, and say hello for us.


The Beauty Of A Healthy Building by Positive Energy

Live from the Texas Society of Architects 2017 Expo and Convention, we're proud to bring you a series of episodes exploring "the multiple dimensions of beauty" through interviews with some phenomenal architects, builders, and consultants. 

This episode features an interview with Dr. Jules Elkins of The University Of Texas at Austin and The East Wall Consulting

Dr. Jules Elkins

Dr. Elkins’s research and teaching is in environmental health, and healthy indoor environments. She is particularly interested in low-dose chemical exposures, especially during the period from preconception to early childhood. Her interests focus on how exposures can be practically and cost-effectively reduced or prevented based on evidence-based models of what interventions measurably work. Specific projects and work includes exposures in schools from poorly ventilated classrooms, exposures from proximity to highly trafficked roadways, and maternal and child exposures from the food they eat. Dr. Elkins is particularly interested in the concept of the Healthy City. Given that we increasingly live in an urbanized world, how can we design away our environmental health problems, and what are the evidence-based outcomes from such design, considering both health and economic metrics? Dr. Elkins also speaks and consults on constructing healthy buildings. This includes choosing healthy materials, optimizing healthy design, and evidence-based outcomes of exposures in indoor environments. This work ranges from green buildings to building for clients with chemical sensitivities.

Big thanks to the Texas Society of Architects and our sponsor Bautex.



The Beauty Of Climate Appropriate Design by Positive Energy

Live from the Texas Society of Architects 2017 Expo and Convention, we're proud to bring you a series of episodes exploring "the multiple dimensions of beauty" through interviews with some phenomenal architects, builders, and consultants. 

This episode features an interview with Peter Pfeiffer of Barley Pfeiffer Architecture

Peter L Pfeiffer, FAIA

Peter Pfeiffer wears many hats.  He is a LEED accredited professional Architect,  a licensed Interior Designer,  Building Scientist and Property Developer & Manager, who has spent the past 36 years designing and developing pragmatic high performance buildings and homes.

 EEBA, the national Energy Efficient Building Association, awarded Mr. Pfeiffer the Conference Chair’s Award in 1994 for his career accomplishments pioneering environmentally sensitive architecture.   In 2004 he was one of the first architects in America to be named a Fellow of the American Institute of Architects for his life-long commitment to "mainstreaming green building in North America”.  He is a founding principal of Barley | Pfeiffer Architecture, a firm recognized nationally for its pioneering use of environmentally responsive design and construction techniques.  Their work has been published both in the United States and abroad in such diverse venues as the Washington Post, The New York Times,  Fine Homebuilding,   Better Homes & Gardens magazine and on-line where they have been awarded “Best Of Houzz” in the Design and Service categories for two consecutive years.  He has been a guest on National Public Radio, the HG-TV network, as well as on The Discovery Channel and This Old House.

The National Association of Home Builders honored him as the “National Green Advocate of the Year” in 2003 for his life-long achievements in “mainstreaming” green building.  Peter has been an active charter member of the NAHB Green Building Subcommittee since its inception in 1999 and has been active in the US Green Building Council’s LEED for Homes program.  In 2006 Residential Architect cited him as one of the 10 most influential residential architects of past decade.  Recently Peter was nominated for the prestigious Hanley Award for his meaningful efforts to advance green building in America. 

Special thanks to Bautex Systems for their generous support of our live recorded episodes at the 2017 TxA Expo & Convention. Be sure to stop by their website, learn about their innovative product, and say hello for us.


The Beauty Of Urban Infill by Positive Energy

Live from the Texas Society of Architects 2017 Expo and Convention, we're proud to bring you a series of episodes exploring "the multiple dimensions of beauty" through interviews with some phenomenal architects, builders, and consultants. 

This episode features an interview with Kristen & Michael Padavic of PSW Real Estate

PSW Real Estate

PSW Real Estate, LLC is a Texas real estate developer that designs and builds communities of high-quality green homes in urban areas. PSW creates homes that offer proximity to work, school and other important resources while implementing energy efficient construction methods and materials. These key elements promote urban density and conservation, reduce waste, and engender social connectivity.

Michael Padavic

Michael joined PSW in late 2011 to develop and lead the newly created design and planning group within the office as part of an initiative to move the architectural development of PSW Homes in house, an aim for greater efficiency and unified vision.

After achieving a Master in Architecture from Harvard University’s Graduate School of Design, Michael honed his skills working for several small to mid-size firms in Chicago, managing a variety of projects from high-rise residential towers and high-end renovations to school restoration and public libraries. He currently holds architectural licenses in both Illinois and Texas.

Specialties: Single family, multi-family and commercial architecture; Sustainable design; Building Information Modeling (BIM)

Kristen Padavic

Kristen moved her family (with Michael, above) to Austin, Texas to join PSW, and Austin-headquartered urban infill home builder after working in Chicago, IL for nearly a decade.  Over the past several years, her architectural team has grown to nearly ten employees, as the PSW team has grown into multiple markets in Texas and Seattle. The team is comprised of a variety of disciplines, including architecture, civil engineering, construction and sales, that all bring unique expertise to the process of designing urban infill communities.


Special thanks to Bautex Systems for their generous support of our live recorded episodes at the 2017 TxA Expo & Convention. Be sure to stop by their website, learn about their innovative product, and say hello for us.


TxA Positive Energy

Season 3 Reflections | Season 4 Preview by Positive Energy

Pour yourself a hot drink, grab a blanket and sit near the crackling logs for this holiday special episode. We're looking back at the last 3 years and looking ahead to our 4th season of the show. Be sure to check out our end of year survey and submit your ideas for episodes in season 4!

Thank you so much for listening to our show for the last 3 years. We plan on delivering more great episodes in 2018 and hope you'll join us for the ride! 

The Beauty Of Performance by Positive Energy

Live from the Texas Society of Architects 2017 Expo and Convention, we're proud to bring you a series of episodes exploring "the multiple dimensions of beauty" through interviews with some phenomenal architects, builders, and consultants. 

This episode features an interview with Darrell McMaster, a builder from Boerne, TX who runs a company called Sustainable Homes of Texas

Darrel has been building homes for over 40 years. He comes from a family of builders, with three generations still active in the home building industry. He is a Master Builder, proud of his craft, and forward thinking in his application of systems and processes.

Darrel says, “the theory is simple if you have to frame on top of the concrete you set up, or build the cabinets that are attached to the wall that you framed you are going to do it right the first time”. 

He's experienced in production, multi-family and custom home building and endeavoring to show that sustainable homes are not only affordable but possible, not only in custom homes but in production homes, as well as multi-family communities.

Special thanks to Bautex Systems for their generous support of our live recorded episodes at the 2017 TxA Expo & Convention. Be sure to stop by their website, learn about their innovative product, and say hello for us.

Knowing & Using VRF by Positive Energy


Apologies for the inconvenience with the last audio file - it appeared to be fine on our side, but was corrupted in the upload process. We appreciate all the feedback and are so thrilled you couldn't wait to hear more! As requested, a new file has been uploaded on a solid connection. Please let us know if you're experiencing any issues and enjoy the episode! 


Positive Energy has built its success around deeply understanding enclosures and how they interact with mechanical systems. We intimately know the HVAC equipment out there. And it hasn’t been easy to get architects, builders, and installers to adopt a new and “unknown” technology. But that’s exactly what we endeavor to do with each project. And you’ve probably guessed by now that we’re talking about VRF here. 

It’s a big deal. It’s the way our industry is headed. And it’s worth understanding and using on your projects. 

In this second of the two part series on VRF, The Building Science Podcast brings you a whole host of information on VRF systems to help you better know, understand, and implement this technology in your projects with a great conversation between our host Kristof and guest John Chavez. Thanks to the generous support of Mitsubishi Electric Cooling & Heating, we're proud to bring you this latest installment of The Building Science Podcast focused on VRF technology and how to bring it to your projects.

Stucco - (Much) More Than Meets The Eye by Positive Energy

Special Edition - Just Released. Listen and learn why you don't want to miss this event! Coming up next Friday 10/13/2017 here in Austin. 

Join Kristof Irwin and guest experts Matt Carlton and Brian Roeder for lively discussion on the surprisingly rich topic of stucco cladding systems. You'll never look at a stucco wall the same way again.

Special thanks to UltraAire for their generous support.

Symposium Details 

Hosted by: AIA BEC: Austin & RCI, Central Texas
Date & Time: Friday, October 13th, 8:30am-5:30am, registration opens at 8:00am
Location: JJ Pickle Research Center, Commons Conference Center, 10100 Burnet Rd, Austin, TX 78758
Price: Early Bird (unitl 9/15) $150/person, General Admittance (9/16-10/12) $190/person, Day Of (10/13) $225
CEUs: 6.5 LU AIA HSW Credits

Intelligent Environments: Building Science & Predictive Analytics Collide by Positive Energy

Join Kristof for a thought-provoking conversation with Dr. Zoltan Nagy on intelligent environments and how building science principles are guiding predictive analytics to shape the future of building and home operations. As more intelligent buildings emerge, occupant-centric solutions to IAQ issues, mechanical issues, and energy issues can be addressed. 

The Intelligent Environments Laboratory (IEL), led by Prof. Zoltán Nagy, is an interdisciplinary research group within the Building Energy & Environments (BEE) Program of the Department of Civil, Architectural and Environmental Engineering (CAEE) in the Cockrell School of Engineering of the University of Texas at Austin.

The aim of their research is to rethink the built environment and define Smart Buildings and Cities as spaces that adapt to their occupants and reduce their energy consumption.

Graphic Mentioned In The Episode

Zoltán Nagy Graphic

Hitting The Reset Button by Positive Energy

It's time to find the reset button. Time to re-examine our view of what we know about delivering conditioned space to our clients, to ourselves. The upside potential in buildings is staggering. From some vantage points, it's astounding and inexplicable why the very places we live continue to be held in a laggard state of performance relative to what's possible. Our industry transition is held captive to an outdated vision. Without a proper vision, our mission, strategy and tactics are ineffective. 

We are all front line advocates, operating within our spheres of influence. What creates effectiveness is knowing why we are engaged in a particular next action and how that relates to moving the industry and the market forward. Why comes first, then what. Many of us can't effectively advocate for best practices in homes/buildings- not because we don't know what to do. Rather it's because we don't know why we need to do what we want to do. If we don't know why then we can't effectively advocate for change with our project teams and the pent-up transition will continue to move forward at a languished pace; albeit inexorably. In this episode Kristof shares some ideas to help us find our reset buttons, or at least pose the idea that hitting reset is worthwhile. 

reset button

Everything You Never Knew About Earthen Construction by Positive Energy

Join us for a fascinating conversation with Stephen Colley on earthen construction. 

Stephen currently practices architecture and runs his own architecture firm and is a long-time practitioner of green design and sustainable living. From 2010-2012 he served as the Program Manager in Green Initiatives for Palo Alto College in San Antonio developing training courses related to sustainable design and construction.

Stephen also participated in the Alamo Colleges Chancellor’s Council on Sustainability helping to write a new more sustainable policy for the Alamo College District.  The new policy was approved by the Board of Alamo Colleges in August of 2012. In his previous position as the Green Building Coordinator for Build San Antonio Green, he developed the criteria for San Antonio’s residential green building program, Build San Antonio Green, recognized by the National Association of Homebuilders as the Green Building Program of the year in 2009, and served on the Mayor’s (San Antonio, Texas) task force on Sustainable Policy as the City charted a significant shift away from conventional building, development, and transportation policy. Stephen was chosen by the National Association of Home Builders as one of the original stakeholders to write the Green Policy for the organization as basis for their nation-wide residential green building program, National Green Building Standard™.

In 2005, he co-authored the Texas Manual on Rainwater Harvesting for the Texas Water Development Board (3rd edition). The Manual is widely distributed and used as a reference for potable and non-potable rainwater harvesting system publications. He is also the former Chair of the San Antonio Chapter of the American Institute of Architects Committee on the Environment, a LEED® Accredited Professional, and President of Earthen Construction Initiative, a non-profit organization to advance and promote earthen construction. 

Photos Mentioned In Episode

Example of earthen construction.

Example of earthen construction.

Earthen Construction Masonry

Earthen Construction Masonry

Compressed earth block machine.

Compressed earth block machine.

Compressed Earth Block Machine

Compressed Earth Block Machine

Notice the earthen construction building in the background still standing after a huge tornado.

Notice the earthen construction building in the background still standing after a huge tornado.

Note: The city in Yemen referred to as “Manhattan of the Desert” is Shibam, in the Hadramut Valley in Yemen. It is designated an UNESCO World Heritage Site.


Earthen Construction Initiative

With a vision that earthen construction is soon recognized as a mainstream building option, the ECI is a member-supported and donor-supported non-profit organization. The ECI website is not yet active, but 2017 memberships are accepted by a check made out to the “Earthen Construction Initiative” along with your contact information at these categories, Student - $10, General Membership - $25, Professional - $50, Companies - $100, mailed to Earthen Construction Initiative, PO Box 39323, San Antonio, TX 78218

For more information, reach out to Stephen Colley.

IEQ Series - Hearing Architecture & ISQ by Positive Energy

Noise can  have an adverse impact on people in offices, classrooms, hospitals and other commercial buildings (European Agency for Safety & Health at Work, 2005), interfering with their daily activities at work or school and at home. People’s performance levels and ability to concentrate can be negatively affected by noise and it can make it harder for them to share knowledge with one another.Join Kristof in this continuation of our IEQ series as he discusses acoustics and sound quality across the architectural spectrum with Keith Simon and John Poesnecker. 

Be sure to check out this wonderful TED Talk by David Byrne on sound and architecture.

View full lesson: As his career grew, David Byrne went from playing CBGB to Carnegie Hall. He asks: Does the venue make the music? From outdoor drumming to Wagnerian operas to arena rock, he explores how context has pushed musical innovation. Talk by David Byrne.

Efficiency Is Not Enough - The Science Of Sustainability by Positive Energy

How good should the building envelope be? How much energy should a building use? Finding answers require putting the building in context with the complex, interconnected, global networks of materials and resource flows in which they exist. Join Kristof for a wide ranging and slightly geeky discussion w Dr William Braham on systems ecology, exergy, emergy, and why a climax forest is a model for power and efficiency. 

Dr. William W. Braham FAIA is a Professor of Architecture at the University of Pennsylvania, where he served as Chair from 2008 to 2011 and is currently Director of the Master of Environmental Building Design and Director of the TC Chan Center for Building Simulation and Energy Studies. He received an engineering degree from Princeton University and an M. Arch. and Ph.D. Arch. from the University of Pennsylvania, where he has taught since 1988. At Penn, he teaches graduate courses on ecology, technology, and design. At the Chan Center, his most recent projects have been the Sustainability Plan, Carbon Footprint, and Carbon Reduction Action Plan for the University of Pennsylvania.

See more of Dr. Braham's work on his website.

Ducts & Sealing & Health, Oh My! by Positive Energy

In this episode, Kristof interviews Sean and Ian Harris, the owners of a duct sealing company called Aeroseal of Austin in Austin, TX. You'll hear discussion on why duct sealing is such a crucial component of healthy delivered air and energy performance of mechanical systems.

Sean Harris has been developing his interest in residential home construction since participating in a remodel project, certified by Austin Energy’s Green Building Program in 2005. With a degree in business administration, Sean combines his interest in green building and knowledge of business systems. Sean oversees the operations of Positive Energy and including product development, quality control, staffing, and marketing/sales. He is also a certified RESNET energy rater and conducts home performance inspections, energy code tests, ECADS, and HERS ratings.


An Interview With John Semmelhack Of Think Little by Positive Energy

Join Kristof in a wide-ranging discussion of building science topics with consultant John Semmelhack of Think Little

John Semmelhack is the owner of Think Little. He is a Certified Passive House Consultant, a member of the Passive House Institute U.S. (PHIUS) Technical Committee, and is a PHIUS Trainer for the Certified Passive House Consultant and PHIUS+ Rater training programs. He sits on the boards of the Passive House Alliance U.S. (PHAUS) and the Passive House Alliance U.S. – Capital Chapter.

John is also a certified Home Energy Rating System (HERS) rater, a Technical Advisor to builders in the EarthCraft House Virginia green building program, and a BPI-certified Building Analyst. He is a graduate of the Leeds School of Business (no, not that “LEED”) at the University of Colorado at Boulder.

Why VRF Matters by Positive Energy

In this first of a two part series on VRF, The Building Science Podcast brings you a compelling argument for why VRF technology matters and will follow up with an episode about how to consider and utilize VRF technology on your projects. Thanks to the generous support of Mitsubishi Electric Cooling & Heating, we're proud to bring you this latest installment of The Building Science Podcast focused on VRF technology and why it's important.