Most of Foulston's work was in the Greek Revival style, but his best known project was the creation of a group of buildings in Ker Street, Devonport in 1821–24. This eclectic group consisted of a Greek Doric town hall and commemorative column; a terrace of houses in Roman Corinthian style and two houses in Greek Ionic; a "Hindoo" nonconformist chapel; and an "Egyptian" library. The Library became the Odd Fellows Hall, and today is a public House. Of these, all but the chapel and the houses survive, and are Grade I listed.
