First, I am honored to be sitting on this panel with such admirable and influential members of the community, so thank you for having me. With my relatively short time in the profession, I cannot claim to speak for the entire architectural community, especially as there are many different perceptions of what makes sustainable design. I'm going to speak more from my own experiences in working and traveling, and what I've learned from others.
In talking about materials and the sustainable cities of the future, I'd like to briefly speak about the relationship between materials and building as a whole, the power of the three Rs, and lastly, on the culture of sustainable design.
If the search for sustainability has taught us anything, it the relatedness and interconnectedness of all aspects of a building. It's very difficult to look at sustainable materials by themselves because they are part of a much larger system, from the site hydrology and microclimate to the design, structure, and building systems. Sustainable materials are only as sustainable as the system they are a part of. For example, rammed earth is a really cool material, especially in the summertime, but it needs to be carefully designed working closely with the structural and civil engineer, because as a material it is extremely sensitive to settling. If a neighbor is growing bamboo next door, there's a possibility the irrigation water could cause the dirt to swell and crack the walls open.
That sustainable design is holistic is particularly exciting to me, since knowing a little bit about a lot is one of things I really enjoy about architecture. To have a holistic building, you need to have everyone on the design team, including the client and the contractor, working together at the same time. Building Information Modeling, or BIM, is helping make some of this possible, where the different members of the design team can quickly react to each others changes.This facilitates experimentation to find the ideal sustainable design. This also suggests that the role of the sustainable architect is shifting from project coordinator to project collaborator.
I'm sure everyone here has heard of the three Rs- Reduce, Reuse, and Recycle. Individually, they are good ideas for pursuing sustainability. But if you look at them as a hierarchy, the three Rs become a much more powerful guide to sustainable design.
Let's take printer paper as an example. At our architecture office, we go through tons of the stuff. Over the years we have switched over to recycled paper, using higher percentages of recycled content until today, we are using paper that is 100% recycled, and we recycle nearly all of it. And thats great! But, recycling paper takes material and energy. You have to transport it, process it, and transform it into new paper to be sold and transported back to our office. Or (flip paper over), I can just use the back side of it.
This is why reuse is stronger than recycle. The back of this sheet is just as blank as recycled paper, but without the energy costs. But it still takes paper to begin with.
The only thing better than reusing paper is using less paper, or not using paper at all. Do you need to print that email or website? Can we send PDFs instead of big rolls of paper drawings? For every sheet you don't use, there's all the energy and environmental impact that is avoided. That's why reduce is the strongest R of all, and results in the greatest savings of material and energy. Now, what if this sheet of paper were a building?
Reduce is the easiest concept, most difficult to do. Take a big step back and ask, does this need to be a hermetically sealed, enclosed, air conditioned space? How much architecture and engineering does a place really need to satisfy its function? In Phoenix especially, where we have fantastic weather, simply using shade, fans, and lighter weight clothing, we can comfortably use our indoor-outdoor spaces most of the year. This is a photo from Richard and Bauer's ISTB building at ASU, where the common spaces and corridors between the various labs and offices are actually outdoor spaces. Shade, outdoor fans, and water evaporation cool the space enough to make it a pleasant place to be even in the middle of the summer.
Reducing architecture takes flexibility from the owners and a lot of creativity from the design team. But as everything is connected, you have to look at the implications of reduction. Instead of reading off a sheet of paper, I could be using a laptop computer. But how sustainable is that laptop? How many sheets of paper is it worth?
Reuse is a little easier. People reuse buildings all the time- its a lot cheaper to retrofit and renovate an existing building than to start from scratch. It's not always easier, which is why most buildings get reused with the same function- houses become houses, offices become offices, and restaurants are replaced by restaurants. However, there are cases where what a building needs to do and what the existing building is are very different. In these moments, the architect has a real challenge and a real opportunity to shine. Demolishing a building produces a lot of waste, and then there is the additional drain of resources and energy in creating a new building. If he or she can keep the existing building, its a huge conservation of material, time, and energy. This building is was a historic mansion in Sao Paolo Brazil, that was converted to a museum of modern art. Not only does the building adapt well to its the new function, but the historic design of the original brick walls are also part of the artwork.
How we reuse buildings is vital to our future cities: the majority of buildings you see today will be around and in use in the year 2050. Another way of looking at that- we will need to meet the needs of a larger society in whatever climatic, energy, or material challenges may come using the buildings we have today. Reuse raises some interesting questions- when is it more sustainable to use more durable materials instead of rapidly renewable ones? I think this is a huge question because it involves expected lifespans of a buildings and communities, predictions on how the use will change over time, and the environmental costs of production compared to the cost of recycling and rebuilding. Is it more sustainable to build a house of bricks or to build and rebuild a house of straw?
When it comes to recycling, I look for minimal processing. What materials take the least amount of energy to make them usable again. The best example I can think of is Christie Tenyke's spiral at Steele Indian School Park, where old concrete slabs were simply broken up and stacked to create landscape retaining walls. There's even a name for the material- urbanite.
There are many products now on the market that claim to have significant portions of recycled content. Usually they are more expensive, which makes me think, what additional energy and material is being spent to make them recycled? What are the environmental costs to recycle this material compared to using virgin material? An example of a good recycled material is steel; in fact, most of the steel used in building frames is recycled. Its relatively easy to recycle and it feeds right back into the production process.
I would last like to touch on the responsibility the architect has in promoting sustainable culture. Architecture is a reflection of culture, but it flows both ways- the design of this library is partially a reflection of the city of Phoenix, but simultaneously shapes the city. Similarly, the pink stucco suburbs define the valley as much as they are defined by the valley. Architects can specify LED lighting and waterless urinals to force users to use less energy and water, and its a good place to start. However, I believe that true sustainability with a fundamental return to the three Rs, is going to take a a cultural revolution on an individual level, and the combined collaboration of the people who define the city.