The son of a Norfolk farmer, he journeyed to India as ship's carpenter from which he earned sufficient funds to start his own building firm in Gray's Inn Road[?], where he was the first builder to have a 'modern' system of employing all the types of sub-contractors internally, on permanent wages, instead of outsourcing the tradeswork as had been done previously.
Cubitt's first major building was the London Institution[?] in Finsbury Circus[?], built in 1815. After this he worked primarily on speculative housing at Camden Town, Islington, and especially at Highbury Park[?], Newington (now part of Islington).
He was commissioned in 1824 by Richard Grosvenor[?], the 2nd Marquess of Westminster, to create a great swathe of building in Belgravia[?] centred around Belgrave Square[?] and Pimlico, in what was to become his greatest acheivement in London. Notable amongst this development are the north and west sides of Eaton Square[?], which exemplify Cubitt's style of buiding and design.
Cubitt's public works included work on the provision of public parks, including being an organiser of the Battersea Park Scheme[?] and a guarantor of the Great Exhibition of 1851, and contributing to the Metropolitan Buildings Act[?] of 1855
After his death, Queen Victoria said "In his sphere of life, with the immense business he had in hand, he is a real national loss. A better, kindhearted or more simple, unassuming man never breathed."