Herbert and Katherine Jacobs First House

Herbert and Katherine Jacobs First House, commonly referred to as Jacobs I, is a single family home located at 441 Toepfer Avenue in Madison, Wisconsin, United States. Designed by noted American architect Frank Lloyd Wright, it was constructed in 1937 and is considered by most to be the first Usonian home. It was designated a National Historic Landmark in 2003. The house and several other properties by Wright were inscribed on the World Heritage List under the title "The 20th-Century Architecture of Frank Lloyd Wright" in July 2019.
The Jacobs House is located in a residential area southwest of downtown Madison, on the east side of Toepfer Avenue between Birch and Euclid Avenues. It is a modest single-story structure, its exterior finished in a combination of brick, horizontal boarding, and glass doors, the latter opening from the rear of the house. It is covered by a flat roof and rests on a concrete pad foundation. Its interior space is 1,500 square feet , and has two bedrooms. The house's original heating system consisted of steam heating pipes laid in the sand base that underlies the main concrete pad. The furnace that provided the steam heat was located in a small basement space under the kitchen.

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