For Phoenix-based architect Wanda Dalla Costa, energy efficiency isn’t just a matter of sustainable design — it’s also a matter of climate justice. As a result of rising temperatures, she says, Phoenix has suffered 1,500 heat-related deaths over a 12-year period. Dalla Costa has seen these trends fall hardest on Indigenous communities living near the city.
“We should be looked at as the canary birds,” says Dalla Costa, who is a member of the Saddle Lake Cree Nation, in Canada. “I often use this concept: who senses the climate changes first? And, of course, it’s often the Indigenous people. And in this case, in the City of Phoenix, they are impacted.”
Dalla Costa has spent nearly 20 years working with Indigenous communities in North America. Today, she teaches at Arizona State University, where she is founder and director of the Indigenous Design Collaborative. She also practices at her firm, the Tawaw Architecture Collective.
Her recent work includes the Gila River project, an effort to develop energy-efficient yet affordable homes with the Indigenous community just south of Phoenix, one of the populations most vulnerable to the city’s rising temperatures. A hallmark of Dalla Costa’s work is its ability to blend a deep-rooted respect for place with a cutting-edge approach to climate resiliency. “I think the days when we could site buildings without any regard to the sun pattern, the wind pattern, the climatic zone you’re in — I’m hoping those days are gone,” she says.
Dalla Costa spoke to Sidewalk Talk about the Gila River project, the Living Building Challenge, and why she prefers smaller-scale projects to big city towers. (You can also catch her on the City of the Future episode, “Energy Efficient Buildings.”)
Could you talk about the Gila River project and the story behind it?
Gila River is an Indian community that’s just south of the City of Phoenix. They’ve lived here for multiple generations, and several hundreds and hundreds of years. I met the governor [of the community] at an event here when I first arrived in Phoenix. And when he found out that I was an architect, he started talking to me about energy efficiency. Straight off, as our first conversation. He had a healthy dose of questioning around the current construction typologies, or the construction methods that were being used here in Phoenix.
In this region, their long history in architecture has been using adobe, which is a very thick and dense material that they used to build very thick walls to be able to keep the heat out in those summer months.
And so, that was the push for him. Culture was a priority. He said, “Can you help us possibly connect back to our original architecture? Can you help us make our buildings more energy efficient?” They have thousands of people that live in that community, and the cost of cooling those homes for Arizona’s hot summers, which can last four to six months, is quite considerable.
Can you delve more into why energy efficiency matters for the people living in these buildings?
Phoenix is one of the fastest-warming cities in the U.S. The impacts of that are many. I started doing research into — it’s quite a morbid subject — but into death, heat-related deaths in Phoenix. And what I found out was that over a 12-year period, there were over 1,500 heat-related deaths in Phoenix.
The City of Phoenix has also done a number of studies on this. What is our reaction? What do we do as a society to help mitigate this potential risk? And so, they did a number of studies on vulnerability. Who is the most vulnerable in terms of heat?
The three factors that they came to was, one, if you live in an isolated setting. Many of our reservations are very isolated. A second one is socioeconomic status. So for instance, if there is a really hot summer day, your air conditioner might be on the brink. Your air conditioning goes out.
Well, most of us would be able to call a guy, spend $800 or $2,000 fixing it. There’s a lot of people that don’t have that privilege.
The third factor was vegetation. The more vegetation you have in a region, not only is it providing shade, but through a process of evapotranspiration, where the leaves and the plants give off water molecules in the air, it cools the air, quite remarkably. A lot of our residents on the reservation don’t have the luxury of having fully landscaped properties. And when you look in the City of Phoenix, there are a number of neighborhoods where you can correlate wealth and vegetation. So this is becoming an issue to me of justice.
The City of Phoenix has wonderful maps available, on where the most vulnerable communities are. And unfortunately, as we were doing our research for the Gila River, we found that both Salt River Pima–Maricopa Indian Community, which is adjacent to the City of Phoenix, as well as Gila River, are both very highly vulnerable communities — beyond most communities in the city.
The Gila River project strove to meet Living Building Challenge Standards, rather than going for LEED, which is industry standard for a lot of green buildings nowadays. Why did the Living Building Challenge feel more appropriate than LEED in this case?
Here at the Indigenous Design Collaborative, we started studying the Living Building Challenge a few years back. This metric system that they’re creating not only took into account the quantitative, the things you can measure, it also took into account the qualitative aspects of architecture.
I think this is one of the really important factors that differentiates Indigenous architecture: what is it about these places from our traditions that we can connect to, and that reflect our belief systems and our values and our worldviews, that we can imbue into our architecture?
When I looked at the Living Building Challenge, it had things like biophilic design. It had beauty, it had spirit, it had words like “culture.” And I have not found words like that in any other sustainable metric system. And I think these qualitative factors are key to the Living Building Challenge and its connection to Indigeneity.
Should architects think about designing a building not just for Day 1, but for Day 101?
We should be thinking about all of our products this way. Landfills are predominantly architectural waste. Is that a sign of our disposable consumerist culture? Are we also throwing away our buildings? Do we need to rethink?
I think of Marie Kondo, and her philosophy of only having the things that you connect with and that you have affinity with and that gives you beauty and joy in your everyday life. And I think if we have that sort of consciousness around architecture, and move it away from the sort of consumerist disposable nature of it, I think that’s one step.
I think a second step would be reconceiving materiality. There’s a big movement around the world connected to reintroducing natural materials. This isn’t just for health and better air quality inside buildings, but it’s also for people’s affinity with nature.
And it goes back to the Living Building Challenge, this biophilic design and connecting with nature and connecting with the systems that are around us. What would happen to our happiness, to our spirit, to what we envision as beauty, if our buildings were closer to mother nature and closer to the earth, made of materials from the earth and that could disintegrate into their site without causing harm?
I think of the adobe structures. There’s no footprint at all from the old architecture. And I think that mindset — it would be really, really wonderful to kind of re-start. I know we can’t go all the way back, but to go back somewhat, to take some of those beautiful principles and bring them forward.
I’ve seen recent studies too that show that living in a building that reflects the values of nature makes you more eco-conscious, in terms of your energy consumption behavior.
When we did the research with Gila River, I remember one of the gals out in the community. I said, “Oh, let’s talk about windows.” And she said, “Yep. Can you make them big? And can you make them connected to this?” She had a lot of sacred landmarks on the horizon. She also had a lot of nature preserves that she wanted to connect the windows to.
And I said, “Fantastic. Yes. Wonderful. Thank you.” And then we asked her about the outside of the house, and we’re talking about exterior choices in aesthetics, and she says, “It’s less important. As long as I have the view of nature, that’s the most important.”
So there’s a psychology of something beautiful in there that’s so ingrained: that community was so connected with nature that the enclosure, the box, the container was less important. The look of that was less important than its ability to connect you with the outside world.
How do you incorporate those principles into the energy efficiency of the building itself?
So for instance, the Gila River House. First and foremost, we start with the cultural analysis. We placed the home in a way that we could connect first and foremost with the cultural aspirations. The openings are very strategic in terms of cultural references to our landscape, sacred landmarks, solstice, and equinox.
Then from there, we begin to layer in the passive strategies. And then it also starts to have these wonderful qualities that we took from their original architectures.
For instance, in Phoenix, when it’s extremely hot, the worst sun comes from the west and the south. So we started studying their original architectures. During certain times of the year, they create very thick walls in those directions. And so the architecture that we’re producing, I said to the researcher and designer that I was working with, “Can we make the west and the south walls different?” We are also now looking at altering the wall systems and making each of the four walls different and reflective of the conditions.
What do you like about working on smaller-scale buildings? What are the issues when you try to scale up?
I’ll give you one example. When I decided to retire my corporate career in architecture, I was working on the tallest tower in western North America. There was such a disconnect between the user group. Indigenous architecture is really a two-way street. They’re teaching me continuously throughout the process. I found that connection with the people of the place — and their ideas and knowledge connected to that place — were missing when we did big buildings. And what instead was guiding that large, 76-story tower was economics. That was the only value and metric that was being used.
For instance, we were supposed to create these big, beautiful, three-story gardens as atriums inside that building. When the owner realized that he wasn’t going to make money from a garden, he turned the gardens into sellable space. It was those types of decisions that I thought: You know what? I need to step away from that and get back to where my passion lies, which is really the people and their stories of the place, and how we connect the people to our histories and our life ways. They’re not always histories. We’re still living. Many people are still living very close to the land. I think that is where I wanted to focus my energy.
How do you bring energy efficiency into bigger buildings in a way that can satisfy the economics, but also results in a radical reduction of emissions?
I think there’s a number of approaches. First of all, it’s very regional, based on our climate zones. I think one of the most interesting buildings I’ve seen in terms of bringing principles — passive design, and maybe original Indigenous principles from early architectures — to the forefront, was a building that was done called the Nicola Valley Institute of Technology. It was with the firm I used to work for, Formline Architecture, and he’s an Indigenous architect, his name is Alfred Waugh. He’s a phenomenal designer.
He took the inspiration from the traditional pit house of the region. In British Columbia, in Canada, they lived underground, partially buried into the earth to keep the cold air out. They would also cover the roof of the building with grasses to keep the heat in for different seasons. He took those principles and he created this school that was buried into a hillside. He planted earth on top, an earthen roof to keep the building well-insulated.
In addition to that, he looked at other strategies of bringing hot air up and out of the building. He took principles from the original teepee, where the hot air naturally rises, so if you give it somewhere to rise and release in the top, the hot air will find its way out. He created a flue system that when the heat came into those south-facing windows, it immediately went up and escaped to the top of the building.
So, you see, he’s taking principles from original architectures and he is bringing them in a very high-tech, modern way to current and contemporary architecture.
So, in terms of climate justice, we should not only rethink the ways that we approach buildings, but the way we live and how that impacts the most vulnerable?
That’s exactly right. Again, who are our canary birds right now? And let’s think about their lifestyle, their livelihood, how they have been impacted. I think our solutions should be directed at the most vulnerable people in our communities — always. It shouldn’t be about economics and about whose voice is the loudest. It should be about us as a society prioritizing the vulnerable, because they are our solution. They are our solution and a path forward.
This Sidewalk Talk Q&A has been edited for length and clarity.