Resilient Design: An Interview with Alex Wilson

September 03, 2014
September/October 2014
A version of this article appears in the September/October 2014 issue of Home Energy Magazine.
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At Passive House California’s annual meeting, Building Carbon Zero Monterey Bay, which took place in Santa Cruz earlier of this year, publisher Tom White had the opportunity to speak to Alex Wilson, president of the Resilient Design Institute (RDI), an organization that creates solutions that enable buildings and communities to survive and thrive in the face of climate change, natural disasters, and other disruptions. Wilson is also the founder of BuildingGreen, Incorporated, in Brattleboro, Vermont, an 18-person company that has served the design and construction industry with unbiased information on environmentally responsible design and construction since 1985.

Tom White (TW): What’s the connection between Resilient Design and Passive House?

Alex Wilson
is the president of the Resilient Design Institute (RDI), the founder of BuildingGreen, Incorporated, and author of Your Green Home and the Consumer Guide to Home Energy Savings.

Alex Wilson (AW): Resilient Design, as I look at it, is about addressing vulnerabilities we face, and creating buildings and communities that will bounce back from interruptions or disturbances, or weather those events better. The relationship to the Passive House movement is that a big part of resilience is buildings that will maintain livable conditions if they lose power or heating fuel—passive survivability. A huge part of that is how well insulated the building envelope is. I love Passive House because it gives you a very clear, measurable, and defined way to ensure that a house will achieve that passive survivability.

TW: What are the inherent principles in Passive House that relate to durability and resilience at the building scale, as opposed to the community scale?

AW: Building science is a key aspect that I’ve been promoting for years, not just through the RDI, but through BuildingGreen and Environmental Building News. I see it [building science] as a part of resilience as well. A resilient home or building is one that will last for a long time. It’s going to be an attractive building that owners want to maintain and keep around for generations. And it needs to not decay. It needs to manage moisture very well, manage airflow. The airtightness requirement in the Passive House program is very strict, as you know. A big part of that, as Wolfgang Fiest will describe, is to ensure that moisture won’t become a problem through air and moisture movement through the envelope. From that standpoint, the building science aspects of the Passive House program fit very well with the model of RD that I support.

Alex Wilson renovated his early 1800s home to achieve net zero energy performance. (Alex Wilson)

The 1812 barn has a group-net-metered solar array on its roof. (Alex Wilson)

Most of Wilson’s home is electric, including the induction cooktop in this kitchen island. (Alex Wilson)

The south- and east-side windows are low-e argon and the north- and west-side windows are quad-glazed Alpen Windows with three low-e coatings. (Alex Wilson)

The 1,500-square-foot home is heated with a mini-split air-source heat pump, which you can see on the far wall here. (Alex Wilson)

TW: What’s the relationship between the Passive House movement and the Living Building movement? One of the builders here said that Living Building is the next bar he wants to reach.

AW: I was just at the BuildWell conference last week in Sausalito and chatted with one of the technical people with the International Living Futures Institute, which manages the Living Building Challenge. I’d never thought about this, but he suggested that I certify the house we just built through the Living Building Challenge. Not the whole thing, but the net energy aspect of it. That’s one of the “petals” that you can do in the Living Building Challenge. There’s a lot more to the Living Building Challenge having to do with issues like materials and red lists. Honestly, I’m not 100% convinced that that’s the best way to address getting toxics out of buildings. For lack of something better, it’s about the best we have. Some aspects of it frustrate me. You can’t use mineral wool without getting a special exemption because of the formaldehyde binders in it. From the research I’ve done on those urea-extended phenol formaldehyde binders in mineral wool, the processing drives out virtually all the free formaldehyde. It’s not going to be an indoor air quality issue, but it’s red listed and becomes problematic. Also I’ve had conversations with the Living Building folks about this from a resilience standpoint—I’d like to see island-able capabilities for electrical systems, solar-electric systems, including battery backup. It can be pretty challenging to put batteries in the Living Building Challenge buildings because of the hazardous ingredients. 

We did a session at last year’s Living Building/Living Futures conference about how to better address resilience in both the LEED rating system and the Living Building Challenge. I’d like to work with both organizations to strengthen those aspects of their programs. Clearly LEED has a lot further to go than Living Building Challenge. To start with net zero energy is pretty far along the pathway toward resilience, water systems as well, and wastewater. To use that as an example—I don’t know if you’ve seen the Bullitt Center in Seattle? It’s an amazing building, really one of the most pioneering buildings built to date. Yet if that building loses power, their wastewater system isn’t going to work. Its foam flush toilets require power to function. That power is provided on a net annual basis with a PV system, but if the grid goes down, that access to electricity disappears as well.

TW: How are net zero energy homes being defined? Is Passive House one of the best paths to achieving net zero?

AW: In my opinion, net zero energy is where we need to be going. To me that’s almost more important than Passive House, although the superinsulated envelope is certainly important. I cringe when I see these Aspen, Colorado-scale houses, massive mansions that have equally massive PV arrays to support their profligate energy consumption. So I like the fact that Passive House addresses that—requiring a certain cap on energy consumption exclusive of the solar that’s delivered. But my goal with buildings in general is to get to carbon zero, carbon-neutral buildings and communities. Generating that power is a very high priority. I’d like to see the Passive House system develop another rating that recognizes net zero energy—I think they’re working on that.

On a broader level—and this gets at another target out there—the Architecture 2030 Challenge, that’s more targeted to commercial buildings. That’s got a goal to commit to creating carbon-neutral buildings by 2030. That’s doable in new construction for modest-size buildings. But it’s simply not feasible with building-generated electricity for big buildings. The Bullitt Center goes almost as far as one could go in achieving that. That’s a six-story building, the first six-story net zero energy building ever heard of. There was a [DOE] National Renewable Energy Lab building that’s net zero, but that’s four stories. That’s also an extraordinary achievement. So I believe that to further the goal of net zero energy with larger buildings and denser communities, we need to be looking at net zero neighborhoods—to broaden the horizon over which we’re measuring energy consumption and production.

There’s a building recently completed in Salt Lake City, a quite large emergency services building, a big commercial building that houses the fire department, police, 911 call center. That’s net zero, based on the building and site and then some additional land that they own where they put in a solar array. So I don’t think that would fit the generally accepted definition of net zero, but I still like it.

TW: Do you see a possibility for a commercial component of a Passive House approach?

AW: I think that would be feasible. There clearly is a focus on Passive House at a certain scale of buildings. Multifamily—it’s very well suited to that. There are some exciting projects happening in Brooklyn, New York—for example, some of Chris Benedict’s work. I’m guessing that in Germany and Austria there are manufacturing facilities that have achieved Passive House certification, but I don’t know the details on that. The advantage with businesses, as opposed to homeowners, is that businesses are used to doing financial analyses based on the bottom line, so they can more easily value the benefit of reduced energy consumption and justify it economically.

TW: How are we going to get homeowners to actually buy Passive Houses?

AW: One of my long-term goals with the RDI is to codify resilience—incorporate it into building codes. The motivation becomes one of life safety, rather than doing the right thing or saving energy only. I could see a building code that directly or indirectly references the Passive House program for achieving that level of resilience—to mandate that. But do it for life safety reasons. Most of our building codes, if you think about them, are related to life safety—seismic, fire, structural codes. They tended to be created after disasters. The seismic code after the San Francisco earthquake of 1906, the fire codes after Chicago’s Great Fire, and so forth. My hope is that we will, as a community and society, have the foresight to really seriously address resilience of buildings before we’re only looking at it in hindsight after some major disaster.

TW: What are the top ways for achieving resilience at the building scale?

AW: Most obviously, energy performance that’s similar to, or identical to, Passive House performance. Through that, one can be fairly sure that the building will maintain livable conditions and keep occupants safe if power is lost. With water, I could see standards for water storage that become incorporated into buildings, to have access to water if the municipal water or power goes down—such as hand pumps or storage. I gather that following World War II, in England it was mandatory for many decades to have water stored in every house, after having dealt with the bombings.

TW: Can you give examples of redundant or diverse systems?

AW: A redundant system would be at a community scale, where we’re used to getting around by car. To have the ability, if the automobile infrastructure breaks down in some way, to have another way to get to the store to pick up supplies by bicycle or walking. Redundant electricity, where you might rely on the grid normally—and there are great benefits of the grid: being able to provide distributed generation and balance loads—but then have a redundant system that you’d have to spend money for, but to provide power when the grid goes down. I’ve got a friend who, when he loses grid power, he connects his normal Prius—not a plug-in Prius—through an inverter that operates the electrical components of his heating system, which is a modest load, so that he can heat his home with natural gas. That wouldn’t work for our house, which is electrically heated with an air-source heat pump, but when the electricity is used only to run pumps or fans, that would be feasible. That’s a great example of redundancy.

TW: Do you have any tips on how to engage builders and designers to work together to apply some of these Resilient Design practices in existing homes?

AW: I guess I’ve taken the approach of teaching them about it through public speaking or articles, but it’s a challenge. When I started the RDI, I felt it would be pretty unlikely that there would be any significant uptake of these ideas before there’s a major disaster—a tragedy. But I wanted to begin developing materials so that if and when that happens, at least we could have a resource to turn to—to crank out materials for things utilities could do, bill stuffers or whatever, or put online.

Right after I started the RDI, [Hurricane] Sandy happened, and that played a significant role in increasing awareness of the need for resilience. So it became a conversation. For example, four or five years ago I was part of a task force in New York City that was trying to green the building codes, put together by Urban Green, and the NYC chapter of the U.S. Green Building Council. [NYC Mayor] Bloomberg wanted this task force to come up with strategies for greening the building codes, including being more adaptable to climate change. I pushed pretty hard for passive survivability, which is what I was promoting at the time. I did a presentation to the committee, and it generated a lot of nods and interest, but it got relegated to a little footnote somewhere about the need for more research into this. But then Sandy came along three or four years later, and all of a sudden this was front and center. A new building resiliency task force was commissioned, and I was also on that. Passive survivability was a key part of the discussions. It became one of the 33 recommendations that came out of that [second] task force, so that’s a huge leap forward—that anyone is even talking about that. It’s pretty far away from any of it being implemented in any way, but the fact that it’s even being brought up is a huge accomplishment.

TW: Reflecting on the beautiful setting around us here in the Monterey Bay area, what we can learn from nature about achieving resilience?

AW: That’s one of my greatest interests in this whole field. My background is in ecological biology. I look at nature and the incredible resilience built into nature and natural systems. That’s sort of the key tenet of ecology—that a diverse ecosystem becomes more stable—because if one species fails, there’s another one that fills that ecological niche, and it becomes a strong balance.

I think we can look to nature for examples of resilience, and that’s a lot of fun to do. Biomimicry plays into that, looking at how nature solves problems. Learning from that and incorporating it into our own buildings and communities and building products—this cork insulation that I used in our house, for example. If you think about cork, it comes from the bark of a Quercus suber, a cork oak tree that grows in the Mediterranean region. The bark evolved in those trees to provide fire resistance to those trees, in a climate that has very dry summers. Wildfires are very common there, so it’s a fireproof protection for the trees. That makes it an inherently fire-resistant product. It can catch on fire with enough heat, but you can put a torch to it for a long time before it will ignite. So that’s exciting to me as a way of looking to nature to design systems.

I was at the BuildWell conference last week, and just blogged today about a presentation there on reinventing concrete and shifting the chemistry from a calcium silicate to a calcium carbonate technology. Actually using cement and concrete aggregate as a way to sequester carbon and build cement plants that are colocated with power plants to use the flue gases as the CO2 source. That’s really exciting. If that can be accomplished by Blue Planet, the company working on that, it’ll be a game changer.

Tom White is publisher of Home Energy magazine. He restores historic homes in his free time.

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