Progress > June/July 2007

Laying a firm foundation

Summer is a quiet time on campus. Most F&ES students leave New Haven for summer internships and research projects around the world, and the pace of life for faculty and staff slows down. But the Kroon building site continues to be a flurry of activity. Over the course of June and July the team from Turner Construction steadily prepared the foundation for this model of green design.

To date, the construction crew has removed 12,000 tons of earth overburden and 35,000 tons of rock. In the end, explosives were never required as the hoe rams were able to mechanically break up all of the rock required to reach the proper elevation. The lowest points of the building are the elevator and sewage ejection pits in the basement level, and before the end of June excavators had cleared the way for concrete to be poured in these pits and for foundational footings.

The first pour of concrete took place on June 25th. Concrete will be a major structural and environmental element of Kroon Hall. The superstructure is composed of concrete except for the glue-laminated timber roof. The walls and floors will serve as a giant heat mass, leading to major energy efficiency gains. In the winter months, the concrete will absorb heat energy and slowly radiate it through the building despite temperature fluctuations from day to night. On a hot summer day, the concrete mass will be cool to the touch, holding and slowly releasing "coolth. "

The concrete contractors are busily assembling the formwork that holds concrete while it cures. Plans are for the first big suspended concrete slab to be poured in mid-September.