When evaluating materials for use in a building, it is obviously necessary to have valid reasons for using the selected material. It is, however, also important to understand the reasons the other candidate materials were not selected, as this is part of the learning process. When my group evaluated materials for the exterior of UM’s Physics and Nanotechnology Building, we concentrated on technologically innovative materials. As a consequence, some of the materials considered were impractical in one or more ways. Two of the materials not selected were Pixel Panels and Terrazzo Lumina.
Pixel Panels is a material consisting of concrete with an array of polymers embedded in it so that it will transmit light. Like most candidate materials, Pixel Panels has some advantages, but it also has some significant disadvantages. While this material has obvious decorative value, it is lacking in practical value. Because the amount of light transmitted is small, the building’s exterior might have a visual warmth at night, assuming sufficiently intense interior lighting was in operation. During the day, however, the additional interior lighting provided by sunlight transmitted through the material would most likely be insignificant.
In Terrazzo Lumina, light-emitting diodes (LEDs) are embedded in concrete and optical fibers route their light to the surface of the material. While such a material has some very interesting interior applications, using it for the exterior of our building was significantly less appealing. A building exterior that “glows” would most likely be quite attractive, but the energy implications make it a less than optimal choice in today’s economy,
While neither of these materials were selected for use on the exterior of our building, understanding why they were not selected can provide some useful insights into what makes a material desirable or undesirable for any given application. We see that materials must have both desirable aesthetic attributes and desirable practical attributes in order to be a good choice, and a concern in either area can eliminate it from consideration.