 In 1811 a building, designed by Peter Atkinson the younger as a council chamber, was erected to the south of the original hall (this is now known as "the Atkinson Room").Then in 1891, another building, designed by Enoch Mawbey, the city surveyor, accommodating a larger council chamber, was built to the north of the original hall (this building is now known as "the Municipal Offices").The council chamber was decorated by Kendal, Milne and Co in the 1890s.