Francis (Frank) W. Wynkoop (January 24, 1902 – September 2, 1978), was an American architect, known for designing school buildings in Pacific Grove and San Carlos.

He also designed oceanfront homes in Carmel Point at the southern city limits of Carmel-by-the-Sea, California, including the noted Butterfly House on Scenic Drive.

[4] In early 1921, Wynkoop opened an office on 1261 American Avenue, in Long Beach and was connected with D. H. Archibald, a city contractor and builder.

[6][7] On July 27, 1924, Wynkoop won second place out of 52 plans submitted in the McGrath & Selover contest under the direction of the Long Beach Architectural Association.

At this time Wynkoop moved his office to the entire eighth floor of the Kress building (listed among the Long Beach historic landmarks).

In 1931, during the Great Depression in the United States, Wynkoop moved with his wife to Seattle, Washington, where he was a draftsman at the Metropolitan Building Company.

[17] On January 25, 1952, Wynkoop placed an ad in the Carmel Pine Cone advertising his architectural office at Dolores Street at 7th Avenue in Carmel-by-the-Sea, with 18 employees working for him.

But the imaginative architect has anchored his sea-sprayed home, built for himself, his wife and three children, firmly in solid rock.He received national attention in numerous newspapers and magazines such as The Californian in 1952,[21] and the National Geographic in 1954[22] Wynkoop lived in the house with his wife Virginia and son Thor until he was forced him to sell the $135,000 (equivalent to $1,535,478 in 2023) house in 1955 to Stephen Kahn for only $15,000 (equivalent to $170,609 in 2023).

[27][28] In January 1954, Wynkoop designed the Morro Bay Union elementary school two-wing addition with eight classrooms at a cost of $140,367 (equivalent to $1,592,565 in 2023).

[30] After selling the Butterfly House in 1955, Wynkoop with his wife and daughter, Nancy, had an office at his residence on Monte Verde Street and 2nd Avenue in Carmel.

[4] In April 1955, Wynkoop designed four six-sided Hexagon buildings for the Atwater, Merced County, Elementary School District.

Between 1967 and 1971, Wynkoop worked with Tongg and Associates on numerous projects across the state including the Haiku Woods property in Honolulu and the Princeville Resort on Kauaʻi.