IWBI’s Signature Interview Series: A Longtime Leader Who Helped Put “IAQ” in Energy Efficiency Innovation

In today’s spotlight, we shine the light on Eric Werling, who led the U.S. Department of Energy’s (DOE) Building America program for the last 12 years and just retired at the end of 2023. Building America is focused on advancing energy efficiency in our homes, which account for about a fifth of the country’s greenhouse gas emissions. In his role as the National Director of Building America at the Building Technologies Office (BTO), Eric faced down each day a massive scope of work. The program’s target market is the entire residential sector, which spans more than 120 million homes across 224 billion square feet of real estate.

Eric and I used to work together during my tenure at DOE. There are two main takeaways for those who know him well. First, he’s a great guitar player and doesn’t miss a chance to strum a tune for his colleagues. Second, he is unmatched in his passion, dedication and vision for expanding opportunities and driving innovation in energy efficiency alongside making improvements to indoor air quality (IAQ). As a recognized expert in efficiency, IAQ and the building sciences, he understands all too well how marrying energy efficiency and IAQ creates significant benefits for American families.

For a lot of years, Eric was one of the few people in government who was championing research and development (R&D) that helped tap into the extensive synergies between residential efficiency and cleaner indoor air. For him, the two were always inseparable. In fact, almost 20 years ago before starting at DOE, Eric led groundbreaking, collaborative work at the U.S. Environmental Protection Agency (EPA) to create the first-ever Indoor Air Quality (IAQ) Design Guide in partnership with The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE), along with other organizations and non-profits. He also led development and launch of the EPA Indoor airPLUS program, which recognizes homes built to advanced specifications that minimize exposure to airborne pollutants and contaminants. Later at DOE, Eric was instrumental in linking the EPA Indoor airPLUS program with the DOE’s Zero Energy Ready Home (ZERH) program, bringing the energy efficiency-IAQ connection full circle.

It’s been five years since I last worked with Eric, but I know he remains as dedicated as ever to advancing residential efficiency R&D while also ensuring that it serves as a net gain for creating better indoor environments. I caught up with him recently to hear how he was able to help pioneer the next phases of his DOE programs, Building America’s efforts to ramp up progress in existing homes and the rapid growth of near zero emissions new homes.

Eric Werling, who led the Building America program at the Department of Energy for the past 12 years, leads a presentation at an ACEEE conference.

Q: Eric, first tell us a little more about the work and mission of the Building America program?
A: Building America may be the longest running and most successful home energy efficiency research and demonstration program in the history of the U.S. It started up in 1994 – coming up on 30 years ago! – incidentally that was the year I completed my Master’s Degree in Architectural Engineering (PSU). The mission of the program has evolved over the years, starting out as a unique collaboration between building science expert teams and homebuilders with the goal of figuring out how to build homes that used half the energy of typical homes back then, without increasing construction costs. Together the Building America Consortia, as they were called in the early years, made huge progress in advancing integrated design and construction processes, and overcoming many practical challenges along the way. Today they’re called Building America Teams, and they’re now focused on technical challenges of retrofitting existing homes to achieve similar savings, at a community scale. Throughout the years, the program has had huge support from industry because it is focused on practical challenges that matter to them by putting expert “boots on the ground.” I love this program!

Q: In recent years, many people have suggested that energy efficiency and improved indoor air quality (IAQ) are at odds. How do you reconcile the two and when did you realize energy efficiency gains could and should go hand-in-hand with IAQ improvements?
A: Yeah, that’s been a persistent misconception. And I don’t blame those who still think IAQ comes with an energy penalty. The problem started back in the late 1970’s, right after the Energy Crisis, when we first started realizing that we would pay a high price for energy use in our buildings. So we set out to improve the efficiency of our homes and buildings. And it turns out the least expensive way to reduce home energy bills is to prevent unwanted heat loss in winter (and the opposite in summer), by sealing up air leaks.

Think of it like this: if it’s cold outside and you leave the doors and windows open, you’ll waste a lot of energy heating up the outside air flowing freely through your house! So back then they sealed up a lot of buildings and saved a lot of energy - with one tiny problem. They didn’t think about how to keep the air inside fresh. That led to “Sick Building Syndrome” in some buildings, and ultimately advancement in building ventilation science and technology. We solved the IAQ problem a long time ago, primarily with practical ventilation systems, but not without a lot of confusion for a lot of people. “You want me to diligently seal all the leaks in the building envelope, then cut a big hole in it and bring in outside air?! Doesn’t that defeat the purpose of air sealing?” people would say. Well, we’ve studied this potential conflict a lot of different ways, and the science-based answer is clearly NO, energy and IAQ are NOT in conflict! All building energy experts today agree. It’s just the old fears and misconceptions that linger.

Today we can cost-effectively seal buildings so tight that energy losses from infiltration are nearly zero, and when you ventilate with heat recovery technology, it gets even better. There really is no conflict, unless you want to cut corners. The only remaining challenge is that doing it right costs a little more up front (as with most things in life). I can’t tell you how many times I’ve heard builders say a “home needs to breathe" – and they use that as misguided rationale for not air-sealing. The truth is you can’t build a home envelope just tight enough to prevent heat loss, but leaky enough for natural ventilation to occur at the right rate year-round. In truth, this old adage is just an excuse for sloppy construction.

Q: We know the Biden Administration has set a new, very ambitious goal of cutting U.S. greenhouse gas emissions in half by 2030. How has that shifted your recent thinking for the Building America program in terms of scaling up and where do you see your program being in five years?
A: Building America has changed a lot, and I’ll cover some of the new focus areas in a minute, but several aspects of the program haven’t changed much at all, namely the collaborative approach to working with industry to develop technical solutions that work for construction businesses, the integrated approach to engineering better performing homes, and the need to measure building performance before you can improve it. The program remains true to these principles, and I think that explains why it’s still thriving after 30 years.

Now for what’s changed:

1. Building America is now targeting existing homes, partly because we’ve achieved the original goal for new homes, and partly because we can’t clean up the housing sector without substantially reducing the cost of energy retrofits

2. Electrifying the building stock has only recently become a clear policy goal, so there’s a lot of focus on heat pump conversions that didn’t used to be part of the plan

3. We have really stepped up the focus on developing solutions that can work for all communities, not just those Americans who can afford to substantially upgrade their homes.

In five years, I think we’ll have proven that energy efficiency retrofits and electrification can be done cost-effectively in those communities with the will to set that goal, all across the U.S. We will also have identified the remaining technical and institutional barriers that prevent wholesale retrofitting of buildings across the nation. Those of us working in this field will still have rewarding jobs in five years! And my hope is there will be five times as many jobs in this field in five years!

Q: I know that zero energy ready homes (ZERH) was a big part of your portfolio at DOE. How is that program helping support deep energy reductions along with IAQ improvements?
A: Yes, I also led DOE’s Zero Energy Ready Homes program, or ZERH, for the last few years. I’d encourage folks to learn more about this innovative program. It’s an incredible story about how government has pioneered innovation in residential energy efficiency, but it’s also a story about putting IAQ and energy efficiency together, because ZERH certification require EPA Indoor airPLUS certification, which includes measures that help ensure a healthy indoor environment. We did this intentionally, because we wanted the program to recognize better homes, both healthier and more efficient. And thanks to recent policy, new homes that are ZERH certified are eligible for a $5,000 tax incentive. That’s going to be a huge driver! I seriously think we’re at the tipping point in residential new construction, which is a great success story, but it will also help us move faster when it comes to retrofitting existing homes.