Clark University of Worchester has selected Waltham-based Genesis Planners and Builders to build a 30,000-sf field house at Granger Field. The facility will house locker rooms, training facilities and 16,000 sf of multi-purpose practice space for recreational sports and Clark's outdoor athletic teams. Chan Krieger & Associates of Cambridge, Geller Sport of Boston and Delphi Construction of Waltham are working with Genesis on the project.