Born in Iowa, Boardman was a resident of Ketchikan, Alaska. An insurance businessman, he served as a member of the Territorial House of Representatives from the 1st District from 1953 to 1954, and as an Alaskan alternate delegate to the 1956 Republican National Convention.
In 1960, Boardman was elected to the Alaska House of Representatives and served in that office through the remainder of the decade. He was the senior member of the House at the time of his reelection defeat in 1970. From 1967 to 1968, he was the 4th Speaker of the Alaska House of Representatives. His predecessor, DemocratMike Gravel, was a U.S. Senator from 1969 to 1981.