The first extensions were made to the rear of the building in 1947 to provide more office space for members.
During the last century extensions and additions to the school were made.
The final extension to the south was made in the early 1950s.
In 1913 extensions were made for 148 patients, which cost £29,833.
No extensions were made to the Park in the 20th century.
In 1992 a further, more modern extension was made to the east wing.
In that same year, extensions costing $94,000 were made to the college.
Since 1912 many changes and extensions have been made to the building.
Since then no extension has been made and the development in the Town from 1947 to 1961 remained slow.
Some 16th and 17th-century extensions to the castle were made.