In 1924, Coate designed the Campbell House located at 1244 Wentworth Avenue in Pasadena, California. He also designed the Robert E. Pond House located at 655 Bradford Street in Pasadena. In 1925, he designed the Stafford W. Sixby House located at 1148 Garfield Avenue in South Pasadena, California, which went on to win a Certificate of Honor from the Southern California Chapter of the American Institute of Architects in 1927. The following year, he designed the Eva K.J. Fudger House located at 211 Muirfield Road in Hancock Park, Los Angeles; it was later purchased by Howard Hughes. He also designed Fudger's residence at 1103 San Ysidro Drive inBeverly Hills, California. In 1930, Coate designed the Elliott Bandini House located at 90274 Via Almar and Via Arroyo in Palos Verdes Estates, California. The same year, he designed the Monterey Colonial style mansion of D.C. Norcross located at 673 Siena Way in Bel Air, Los Angeles; A.E. Hanson was the landscape architect. In 1931, he designed the Monterey Colonial style Pasadena Town Club located at 378 South Madison Avenue in Pasadena, California. In 1933 and 1934, he designed the private residence of film producer David O. Selznick in Beverly Hills. In 1934, he designed the W.B Hart House in Pasadena, California and the Parley Johnson House in Downey, California. The same year, he also designed the private residence of Henry W. O'Melveny located at 1709 Stone Canyon Road in Bel Air. In 1939, he designed the Everett Sebring House located at 612 Berkshire Avenue in La Cañada Flintridge, California. He renovated and enlarged the Jack Warner Estate. In 1941, he designed the private residence of Robert Taylor and Barbara Stanwyck located at 1101 Beverly Drive in Beverly Hills, California. Together with Silas Reese Burns, Sumner Hunt and Aurele Vermeulen, Coate designed the headquarters of the Automobile Club of Southern California located at 2601 South Figueroa Street from 1921 to 1923. Together with Reginald Davis Johnson and Gordon Kaufmann, Coate designed the All Saints Episcopal Church in Pasadena, California in 1923, listed on the National Register of Historic Places. In 1924, they designed Camp Arthur Letts, named after Arthur Letts, of the Boy Scouts of America in the Hollywood Hills. The same year, they designed the Hale Solar Laboratory and the Griffith House in Pasadena. In 1924-1925, they designed a new building for Saint Paul's Episcopal Cathedral located at 615 South Figueroa Street; it was demolished in the 1970s. He also designed the private residence of H.C. Lippiatt & M.P. Taylor in Bel Air, Los Angeles. His achievements include works that are listed on the U.S. National Register of Historic Places. These include :
Coate had a beach house he built in 1935 located in Emerald Bay, Laguna Beach, Orange County, California. He had 2 sons, William Bleecker Coate and Roland E Coate, Jr., also an architect, and one daughter, Suzanne Coate. He died on October 17, 1958 in San Diego County, California.
