From 1976 until 1996, Carpenter created sculpture for the Washington National Cathedral, in Washington, D.C. He began there as a seventeen-year-old shop assistant, became a freelance sculptor, then the Cathedral's first Sculptor-in-Residence. Ultimately Carpenter designed over 500 of the permanent limestone sculptures that adorn the building. These include the grotesques and gargoyles seen below.
Included among his works on the building, are 320 angels with musical instruments, numerous boss stones and capitals, a fountain ornament, and the Cathedral's final tympanum. This tympanum, titled "Alleluiah, He is Risen," crowns the entrance to the crypt and depicts the miracle of the empty tomb.
In addition to the Washington Cathedral, Carpenter has created sculptures for other historic churches. Saint John's Church, "The Church of the Presidents," on Layfaette Square in Washington, DC, contatins two sculptures; and Canterbury Cathedral, in Canterbury England, has two processional crosses Carpenter created for the installation of the Archbishop.