The Acton House - 12

Tom Silva tests out the old-fashioned v-shaped gutter he made for the front porch, then takes us on a tour of the house, explaining his preparations for the spray-in insulation. Most of these are like for any other insulation job, like his use of vent chutes to keep the roof cool, though he did have to cover the windows to protect them from overspray and put up one side of the interior walls for those rooms he wants insulated for sound. Paul Kennedy explains the challenges he faced in working with the house's steel studs. Our master carpenter follows the spray-in urethane insulation process - from mixing the two-part formula on a truck to spraying it into stud bays, where the liquid expands to 100 times its volume, to cutting away the excess to allow for the drywall. The system not only insulates, but acts as a vapor barrier and air sealant as well. Outside, painter George Hourihan reveals some tricks of the trade.