Well planned on-site precasting procedures contributed to the on-time completion of Dartmouth College's new field house. Designed in reinforced concrete by Pier Luigi Nervi, the new structure is essentially all roof, its thin shell barrel arch enclosing over 93,000 square feet of playing and practice area and other sport facilities. Since the roof pans account for over two-thirds of all the concrete in the vaulting roof structure, it was apparent to all concerned that foresight in laying out and scheduling the precasting operations would pay off in keeping the job on schedule. Therefore in the fall of 1961, the contractor, Wexler Construction Company of Massachusetts, started casting of the roof pans, and worked throughout most of the winter in a covered casting shed. By spring of last year, as open work began again, the contractor had stockpiled enough pans to start erection. As the roof was being constructed, careful scheduling of precasting always kept the pan supply well ahead of erection requirements.