Ernest Lynn McCoy was born in 1906 in Bakersfield and attended Kern County Union High School. McCoy attended the University of South California College of Architecture. From the mid-1930s to the Second World War, McCoy apprenticed with Charles Biggar, starting as a draftsman and working up to acting in capacity of architect supervision for Biggar (AIA Membership Fire for Ernest McCoy). After the war, McCoy opened his own private practice in the Hay Building of Bakersfield, and became a member of the AIA in 1947. A son, Robert McCoy, followed Ernest into the practice of architecture in Los Angeles (AIA Membership for Ernest McCoy).