Precast - Fact or Fiction?
Greg Winkler, AIA, LEED AP, Executive Director of Mid-Atlantic Precast Association (MAPA) dispels common, preconceived notions in Bad Things Architects Say About Precast Concrete (and Precasters!) for the MAPA Newsgram, May 2011.
We selected three of our favorite misconceptions added a CarbonCast perspective. We welcome your thoughts as well.
Precast isn’t green.
Some architects cite the amount of CO2 emissions produced during the production of cement as a reason that precast is not a sustainable product.
Recommendation: Carbon footprint is not the sole definition of sustainability. Both the IgCC and LEED are transitioning the market to the fuller idea that sustainability = high performance. Energy efficiency, durability, and low life-cycle costs are where all the money–and environmental impact–occur. Precast excels in the high performance arena.
AltusGroup says: By using C-GRID® carbon fiber grid as a reinforcing material, CarbonCast® technology amplifies many qualities that enables precast to contribute to LEED® certification by design. You may view a chart showing potential LEED point contributions for CarbonCast enclosure systems and double tees or see a complete list of benefits.
Precast is too risky. I already know how to do steel and brick & block.
Architecture is a business. Architects have standard details, specifications, construction administration history, and comfort with building construction they have done before. To some of them, precast represents a liability and profitability risk.
Recommendation: Although precast requires an early commitment in the design phase, the payback is that most of the detailing is performed by the precast engineer, as well as early pricing and schedule inputs and consultation on how to control costs. One large risk reduction for the architect: elimination of the cavity wall and an easy solution to the edge-to-edge insulation requirement. Precast also allows the construction of multi-product facades without worrying about differential movement, expansion joints, and waterproofing closure and continuity issues. For winter construction, precast largely eliminates the issue of cold-weather procedure change orders and weather delay claims. Overall, precast is less risky for the design professional.
AltusGroup says: An ARCHITECT magazine R+D award-winning technology, CarbonCast® Enclosure Systems and Double Tees integrate ultra-strong, noncorrosive C-GRID® carbon fiber grid into precast during fabrication. C-GRID reinforcing is an “enabling technology” that allows CarbonCast to be thinner, lighter, more durable and less costly overall than conventional precast and other building systems.
I don’t like (pick one): The look of thin-brick, panel joints, exposed concrete corners, muted colors, etc.
Architects who make this complaint either have false preconceptions or do not understand the versatility of precast.
Recommendation: Precast is a great mimic material. It can be almost anything you want it to be (though sometimes for a cost). Tell the architect that all of these complaints are design decisions under his control. Ask him to design the building and tell him you will work with him to craft the details that concern him.
AltusGroup says: Our detailed project portfolio offers an in-depth glance at the aesthetic versatility CarbonCast technology provides any commercial application and parking structure. A few of our notable projects include multiple recipients of the 2010 GreenSite Project of the Year Proximity Hotel, the nation’s first-ever hotel to receive LEED Platinum Certification and Willow Creek Elementary School.
