Waldron Faulkner, 81, a Washington architect for nearly 35 years who won numerous design awards for his work on institutional buildings, died Friday in his Washington home. He had cancer.

His last work before retiring in 1968 was the conversion of the Old Patent Office into two museums, the National Collection of Fine Arts and the National Portrait Gallery. He received both regional and national homor award from the American Institute of Architects for this work.

Mr. Faulkner also received awards from the Washington Board of Trade for his design of a number of buildings, including George Washington University, Suburban, Providence, and Holy Cross hospitals.

Other major architectural commissions were the original campus of Madeira School in Greenway, Va., and the headquarters of both the Brookings Institution and the American Chemical Society.

Mr. Faulkner was active in civic affairs, serving as president of the Washington Urban League from 1938 to 1941, and president of the Washington Housing Association from 1947 to 1950. He was secretary of the board of the Lisner-Louise Home from 1954 until the time of his death.

He was a fellow of the American Institute of Architects, and was president of the Washington chapter of AIA in the early 1940s.

Mr. Faulkner was born in Paris, France, the son of a Connecticut Yankee painter who moved in the circle and genre of John Singer Sargent and Frank Millet.

After going to Yale University, where he earned a bachelor's degree in philosophy and studied engineering, he become interested in architecture and stayed on to earn a bachelor's degree in 1924 from the School of Architecture. He was awarded the AIA student medal and a fellowship, which allowed him to study for a time in Rome.

He worked for several years as an architect in New York City before coming to Washington in 1934. He formed a partnership with Slocum Kingsbury five years later and retired from the firm of Faulkner, Stenhouse, Fryer and Faulkner in 1968.

Mr. Faulkner was a member of the Cosmos Club, and had served as its president in 1953. He also belonged to the Literary Society of Washington, the Chevy Chase Club, and the Gibson Island Club. He was president of the Yale Club of Washington from 1943 to 1944.

He was the author of a number of works on the use of a color in architecture, including a 1972 book on the subject, "Architecture and Color," published by John Wiley and Sons.

Mr. Faulkner had been a member of the Washington Cathedral Chapter during the 1960s, and was a senior warden of St. Margaret's Episcopal Church in Washington during the 1970s.

Survivors include his wife, Elizabeth F., of the home; two sons, Winthrop W., of Washington, and Avery C., of McLean; a daughter, Celia F. Clevenger, of Washington ; a brother, Louis M., of Washington, Conn., and 10 grandchildren.

The family suggests that expressions of sympathy be in the form of contributions to the Washington Cathedral, St. Margaret's Episcopal Church, or the Lisner-Lousie Home. CAPTION: Picture, WALDRON FAULKNER 1965 photo