The Louis Christian Mullgardt collection consists of specifications and drawings for the Evans residence in Mill Valley, drawings and a photograph of the Court of the Ages (from the Panama Pacific International Exposition), drawings of a commercial building in Honolulu, and photographs of an unidentified residence in Piedmont, California. The collection also includes photographs and photocopies of specifications and correspondence for the Stevens residence in San Jose. These documents are reference copies of privately held materials, and the Environmental Design Archives does not hold copyright on the records.

The Mullgardt collection is comprised of numerous individual donations. Records of the Evans residence were donated in 1952 and 1970, and the Stevens residence materials were donated in 1989.