The Robert and Esther Armstrong House testifies to Grant Wood's considerable talents as an architectural designer and the impact of his Regionalist Credo on those designs. Although best recognized for his paintings, Wood had considerable interest in and talent for interior and exterior design, and the Armstrong House is one of many (fourteen are documented) such projects he undertook in Cedar Rapids and one of two residences in that city that he designed in their entirety. Wood ardently believed that art and architecture should reflect the past traditions and craftsmanship and native materials of an area. In designing this house and in directing its construction, he based its exterior and interior on early stone houses near Stone City, Waubeek, Viola, and Manchester and utilized locally quarried building stone in its construction. The property is significant under Criterion C as the work of a master designer.

The exterior of the house is made from stone quarried at Stone City, transported to Cedar Rapids by boxcar, and hand-hewn by two 80-year-old skilled stonemasons chosen by Grant Wood. Large lintels which weighed between one and two tons each were hoisted into place by derricks. Large stones were also used at the front gate to protect the entrance gate which Wood designed. He also designed the garden seat from three large pieces of stone, and used stone for the garden wall. Two boxcars of stone were required for the house and one boxcar for the garden wall. - NRHP