The CASE for Sustainable Building Materials

by Mary Martialay on November 22, 2011

Earlier this year, the Center for Architecture, Science, and Ecology (CASE) received a 2011 R&D Award from the American Institute of Architects for one of their newest research projects – the Solar Enclosure for Water Reuse. Here are a few thoughts from the award announcement:

According to the World Health Organization and UNICEF, approximately one in eight people lack access to safe drinking water. In the United States, the building industry alone consumes 12 percent of all water withdrawals, and another 49 percent of water is used to create energy to power the built environment, according to the U.S. Geological Survey. In the face of such overwhelming evidence, the Center for Architecture Science and Ecology—a partnership between Skidmore, Owings & Merrill and Rensselaer Polytechnic Institute—developed a prototype that conserves energy and uses solar energy to passively filter graywater. And the system isn’t stashed in the basement or hidden from view. Instead it takes the unexpected form of a glass façade.

Sounds about right. The CASE invents materials that incorporate systems – like generating electricity, gathering water, treating sewage, or filtering air – directly into building materials for roofs, walls, windows and interior partitions. Their signature is an elegant solution that, as the award announcement recognizes, puts sustainability front and center in design.

I recently had a chance to visit the lower-Manhatten offices of the CASE in its lower-Manhattan offices (co-hosted by Rensselaer School of Architecture and architecture firm Skidmore, Owings & Merrill in the SOM offices on Wall Street). Their space is sort of half-office/half-lab and it was peppered with interesting prototypes and projects in progress. It was fun to see so many of their inventions in one space doing their thing.

For example, the picture at the top of this post shows one of the prototypes – an “Integrated Concentrating Dynamic Solar Facade” -undergoing tests in an office window. The solar facade – which can be used for windows or facades – contains solar concentrators that track the sun and simultaneously generate electricity, gather heat from water circulating through the system, and diffuse light coming into a building.

In the top picture,  you can see two working solar energy collectors on the right – a photovoltaic cell is fixed at the apex of the glass and flexible tubing channels water through the system, and on the left is a sensor measuring the amount of light entering the system.

This closeup shot (above) shows the frontside of a collector with the lens and flexible water tubing surrounding the photovoltaic cell. As they refine their design, CASE researchers are gathering data on how much heat and eletricity the system gathers, as well as how much heat is lost as it travels through the system.

CASE Director Anna Dyson said CASE researchers are “expert integrators.”

We solve problems. We do something different because what’s out there isn’t good enough. We look at what’s out there that we incorporate in the solution, and we integrate it with building materials.

CASE not only develops building materials, it also trains an up-and-coming generation of architects to look across disciplines to solve problems. Center director Anna Dyson said that while CASE students (a mix of undergraduates, master’s and PhD candidates in architecture) are specialists within their field, “their specialization is in integration.”

Our students are expert integrators, expert organizers, they have taken science, they’ve taken math, social sciences, art, and architecture. We see very few people in the field who have the ability to integrate that our students are developing.

For example, when CASE built the first generation solar facade unit (several successive generations have since been built), they pulled together an existing mirror tracking system, a furnace lens, and the perfect solar cell for the job, but at the time, the solar cell was only available for satellites. Since they couldn’t buy it, a professor on Rensselaer’s campus actually had to build their first solar cell by hand. The CASE researchers had to consider: Would that cell eventually be available for commercial use? Would it be affordable at that point? Were better options coming down the pike?

Dyson and CASE Assistant Director Jason Vollen will also tell you that the lack of such “blue fingers” abilities in the building field is an impediment to greater integration of sustainability in building materials. As Vollen put it:

If you don’t have policies, and you don’t have the codes, then you can’t have the progress.

Dyson and Vollen have a lot to say on the subject, and they hope their insight and experience will play into a longhaul revolution in the philosophy of the building professions.

But please, let me not neglect my guests – there’s more to see.

CASE is working on a “phytoremediation system,” a modular wall unit that supports common house plants capable of filtering “off-gas,” the toxins emitted by modern furniture, office equipment and finishing materials in office environments (that’s Vollen in front of a prototype unit). In another example of integration, CASE researchers came up with the idea for the system, and then combed existing research to determine which plants best filter formaldehyde (English ivy, as it happens).

The plants create oxygen, while bacteria growing on their exposed roots break down volatile organic compounds (VOCs) and other pollutants. CASE estimates that the system is capable of lowering VOC levels found in typical offices by more than 80 percent, reducing the load on mechanical ventilation systems, and cutting HVAC energy consumption by up to 60 percent.

Another idea in the works combines knowledge of ceramics, and thermochromatic coatings with the particular sun position and climate in a given location to produce the “high performance masonry system.”

You can see some of the sample bricks (mounted on a conference room wall) on the left. An architect designing a building can choose from a palette of bricks to tune the absorption or diffusion of heat on a particular building based on the climate, orientation and even height of an exterior wall. As with the integrated solar facade materials, water can be piped past the underside of the bricks to heat or cool it as part of the domestic heat/hot water system of the building.

CASE regularly earns accolades and awards for their work – the phytoremediation system won a 2009 AIA R&D Award to mention one – and, while they’re not interested in commercialization, they do hope to see each of their inventions installed in an actual building – which is called a “test bed.” One of the advantages of the partnership with SOM is that they are regularly approached by architects working on a project that holds potential as a test bed for the CASE designs. It is a long road from drawing board to prototype to installation in a real live building, but, from what I hear, the destination is in sight.