Hopper was first employed by Walsh Porter who was a close companion and advisor to the Prince of Wales (who later became George IV). One of Hopper’s first jobs for Porter was to help with alterations and decorations on his villa, Craven Cottage in Fulham, London.
Hopper was eventually introduced to his Royal Highness the Prince of Wales who first employed him in many alterations at Carlton House.
One of Hopper’s more renowned projects was a conservatory which was specifically built to host a fete in honour of the Allied Sovereigns.
Built in 1814 the finished article was described as light and elegant but with a florid gothic style. However it's most famously remembered for the rather extravagant inclusion of a narrow tank running through the centre of the supper tables containing live fish.
After that Hopper’s fame grew substantially and he was hired for a number of high-profile projects including:
Slane Castle for Marquis Conyngham
Gosford Castle for Lord Gosford
Gatton Park for Lord Monson
Easton Lodge for Viscount Maynard
Kinmel Park for Lord Dinorben
Llanover Court for Sir Benjamin Hall Bart
Alton Towers for Earl of Shrewsbury
Danbury Palace for Mr C Grey Round Esquire
Penrhyn Castle for Col. Pennant
As well as this, he also helped in the construction of a number of London buildings and worked on Windsor Castle. He was also county surveyor for Essex for many years.
Hopper died on 11 August at Bayswater hill at the age of 81. The Illustrated London News said of Hopper in an obituary published shortly after his death:
'Mr Hopper was married; and his widow, with two daughters, survive him. In manners courteous and affable, generous and charitable to a fault few men have passed through an active long life with greater credit and general esteem than Thomas Hopper.'