He was known for playing comedic blue-collar workers, including his recurring roles as Mr. Treeger, the building superintendent, on Friends and the manager of a muffler shop on HBO's Lucky Louie.
[5] Before becoming an actor, Hagerty worked at a restaurant in Evergreen Plaza and a Shell gas station and repair shop on Western Avenue.
[5] He went on to co-write and co-star in three revues on the troupe's mainstage during the 1980s (Also Available in Paperback — A Retrospective, Orwell That Ends Well, and True Midwest, or No, But I Saw the Movie).
[5][8] He was recognized for his small character roles in a wide range of popular comedies, including Martin, Cheers, The Wayans Bros., Curb Your Enthusiasm, Friends, Seinfeld, and The Wonder Years.
[3] He maintained ties to his hometown, appearing at community fundraisers at the Beverly Arts Center and the local Catholic church.