In 1912, transportation was shifting from horse and buggy to automobile. After guests dismounted from their carriage under the porte-cochere, their carriage was driven to the Carriage House where the dust was washed off, the horse cared for and it was then turned around in preparation for departure. Recent repair work (2011) uncovered remnants of a large turn-table apparatus in the floor of the carriage house that was used to spin cars or carriages around.
The Carriage House was built of the same materials as the main house. Originally, the second floor was an apartment for the cook and the chauffeur, who were married. During the Anderson years, a nanny lived there. During the Quie years, a refugee family from Vietnam lived here: Yen and Dong Trinh and their baby daughter Uyen. This area has now been remodeled as office space for the Residence staff.
The first floor remains as a garage and storage area. The basement houses the natural gas and hot water heating systems for both buildings.
The large lot to the west of the Residence was donated in September 1965 by the Alice O’Brien Foundation to use for additional parking spaces. The grounds now total 1 2/3 acres.