In New York State’s historic Hudson Valley, old residences often grew by accretion. This house located in the popular weekend community Garrison was erected in the middle of the 18th century as a working farm building; through the 1990s it expanded to include new wing and freestanding structures. Ultimately, the multiple additions yielded a pair of closely adjacent buildings, so the property’s 1997 renovation carried that trend to its natural conclusion. The construction of a children’s bedroom and a rear porch merged the two buildings into one large home, which features an intuitive, open plan that suits the modern rhythms of the client. Yet both inside and out, the house’s architectural shapes and material textures also reflect the human scale and environmental harmony of a house untouched by time.