Plot: With 75 percent of the new prefabricated house being built in a workshop, host Kevin O'Connor opens the show at Bensonwood in New Hampshire, where today it's all hands on deck. General contractor Tom Silva meets up with builder Tedd Benson to see how his crew prefabricates interior and exterior wall systems, while next door in the timberframe shop, job captain Mark Roentsch shows master carpenter Norm Abram the assembly of salvaged Douglas fir and live oak timbers that will frame the dining area