Style and Sustainability of Precast Concrete
Learning Objectives:
- Describe the use of precast concrete in terms of building performance, sustainability, and construction benefits.
- Explain how precast concrete solved numerous design and sustainability considerations for the case study subject, the Perot Museum in Dallas.
- Discuss the effect of precast concrete on green building certifications and ratings.
- List the general attributes of cements and concrete mixes, and the selection criteria used for the case study project.
Credits:
Precast concrete façade cladding systems have been used for significant works of architecture, and a contemporary example is reviewed in this continuing education article. The case study—the Perot Museum of Nature and Science in Dallas—is examined in detail to show how its precast concrete panels can contribute to design excellence, including sustainability, high performance, efficient construction, and advantages for occupant health and safety. Examples of the benefits of precast concrete include durability, low maintenance costs, good life-cycle performance, high thermal mass, acoustical isolation, and resistance to air infiltration and weather.
Choice of cements, aggregates, coloration, and other additives for both performance and aesthetic characteristics is an important part of developing any architectural solution. General guidelines are presented for determining the concrete mix, with attention to the specifications for the new museum.
In many projects utilizing precast, as was the case at the Perot Museum in Dallas, an important attribute of a precast panel mix is to minimize panel or unit weight without compromising the durability and sustainability of the cladding. The resulting mix may be compared to ordinary portland cement concrete to determine weight and material savings. This simple consideration will impact the building's green attributes, construction cost, and other variables.
A number of aesthetic benefits are possible with the use of precast concrete façades. Among the visual considerations outlined is the use of integral color throughout the precast slabs. In many typical applications, the use of pigmentation is isolated to an exterior portion and sandwiched against the uncolored grey cement, which typically comprises the interior. Integral color affords some advantages in design expression.
The precast concrete façade cladding on the new Perot Museum of Nature and Science in Dallas is used to aesthetic advantage by Morphosis Architects, with Pritzker Prize-winning architect Thom Mayne. Photo courtesy of Holcim (US) Inc. |