It was renovated and added to by noted architect R. Brognard Okie in the Colonial Revival style. The original log section of Merestone House dates to between about 1720 and 1734. It is a two-story, three bay, structure measuring 20 feet by 24 feet. A two-story, two bay, frame addition was built between 1725 and 1750 and measures 19 feet by 18 feet. A two-story, one bay, wing was added between about 1802 and 1806. The house was renovated in the Colonial Revival style in 1941-1942. At the same time, Okie built the 1 1/2-story, three bay, frame guest house / garage on the stone foundations of a barn dated to 1806.