Sited on a bluff overlooking the Beaver River, the gable-roofed house has a pedimented portico supported by four Tuscan columns on both the front and rear elevations. It has a raised basement and paired corbeled, interior end chimneys, each with two pointed-arched windows in the gable ends. The white-painted brickwork is laid in a Flemish bond pattern. Fluted Ionic columns and Greek-style ornament flank the entrance doors. The first story has four rooms with a central hall. The kitchen in the raised basement is linked by a spiral staircase to the first floor and the attic. Built for James and Mary Arbuckle and their six children, the house was purchased in 1887 by Samuel R. Dunlap, who ran a brewery and hotel in Bridgewater; his name has come to be identified with the house.