AMHERST, Mass. – A massive and intricate wooden dome temporarily adorning the plaza of the Fine Arts Center at the University of Massachusetts Amherst was engineered and constructed by UMass students over two semesters as part of a wood design studio class.
Known in technical circles as a timber grid shell, the structure is the end product of a course taught by Peggi Clouston, associate professor in the building and construction technology program at the university. Thirty feet in diameter, the 3,500-pound shell rises to 11 feet at the center. The 52 longest laths in the structure measure 41 feet.
“We worked out the engineering and construction details last spring and this spring we focused on fundraising and fabrication,” Clouston says. “It is really wonderful to see the shell take shape after promoting and imagining it all this time.”
The shell was a collaborative effort by an interdisciplinary and multicultural mix of UMass Amherst students. As many as 35 students from many fields and backgrounds across campus were involved in the shell fabrication. Fabrication of the shell was headed up by building and construction technology adjunct faculty member John Fabel.
Clouston says, “The wood is local white ash, which is, in itself, a special story. White ash is the perfect material to use for this dome because it is very strong yet pliable. It is also threatened by a small insect called the emerald ash borer and finding markets for it is a national forestry objective.”
She adds, “By constructing this dome, we are working to create new markets for local trees to help defray the costs of thinning and to thereby help ensure the health of local forests. It will also create jobs in rural communities and spur economic development for the local forest industry.”
The grid shell is intended to demonstrate the possibilities of using wood in high-tech applications and to promote awareness of new wood composites in recent large-scale construction projects, like the Design Building currently under construction just up the hill from the plaza.
“The two projects are actually related,” says Clouston. “The plan is to use the shell as a backdrop for a student public art exhibition on what makes the Design Building so special.”
The Design Building is the first of its kind in the U.S. employing cross-laminated timber panels—a new wood composite that is emerging as a sustainable alternative to steel and concrete in large-scale construction applications. “The massive panels offer significant environmental benefits,” says Clouston. “They store carbon and create far less pollution in manufacturing than steel or concrete, which is normally used to frame non-residential structures.”
Several industry sponsors donated money towards the project and a UMass MinuteFund campaign https://minutefund.umass.edu/project/1890 successfully raised $3,550 to date to pay for materials and equipment needed. The wood laths, valued at approximately $10,000, were donated by local companies Lashway Lumber and Ponders Hollow.
The timber grid shell will be on display for at least a couple of months, says Clouston.