The £18m project includes the complete refurbishment of Room 32, the largest within the National Gallery, as well as refurbishing parts of the existing basement and ground floor areas to provide new offices, meeting rooms and behind-the-scenes facilities.
The original building was designed by William Wilkins in the 1830s. Willmott Dixon Interiors’ project will be delivered in the extended part of the gallery designed by Edmund M Barry that was completed in 1876.
The refurbishment works have been designed by architect Purcell and funded by Tetra Pak billionaire Hans Rausing.
Willmott Dixon Interiors managing director Graham Shaw said: “We’ll be able to use our track-record of transforming historic buildings, such as the Commonwealth Institute, for the benefit of the National Gallery. Our team are really looking forward to enhancing another London landmark so that it can be enjoyed by millions of people over the coming years.”