In 1835 the British Government agreed that a new Government House in Sydney had become a necessity, and the royal architect, Edward Blore, was instructed to draw up plans. Construction commenced in 1837 and was supervised by colonial architect Mortimer Lewis and Colonel Barney of the Royal Engineers.
In 1835, the British government determined that a new Government House was necessary for Sydney, leading to the appointment of Edward Blore as the architect and the commencement of construction in 1837 under the supervision of Mortimer Lewis and Colonel Barney.