Royal Architectural Museum

The museum was established by a group of architectural professionals led by Sir G.G. Scott in 1851 and it occupied several locations including the South Kensington Museum until 1869. At that time, it moved into a former residence at 18 Bowling (or sometimes Bowley) Street that was renamed in 1870 to Tufton Street located behind the Dean's Yard at Westminster Abbey. Architects Ewan Christian and Joseph Clarke designed the new museum.

Illustration of the facade from an 1884 guide to the museum for students

All of the interior decorations were furnished gratuitously. Salviati decorated the head of a panel to the right in the lobby with Venetian mosaics after a design by Clayton and Bell. Unfortunately, an illustration of the mosaic could not be found.

1872-73 view of the casts of sculptural details displayed in the museum

The museum was disbanded in 1915 and the collections were dispersed mainly to the Victoria and Albert Museum. In 1916, the National Library for the Blind moved into the building, which was demolished and consequently rebuilt in 1935.

The building currently at the NW corner of Tufton and Great Peter Street.

Sources:
The Art Journal: The Illustrated Catalogue of the Industry of All Nations. 16. London: Virtue & Co., 1869. 285.
Thornbury, Walter and Edward Walford. Old and New London: Westminster and the western suburbs. London: Cassell, Petter and Galpin, 1891. 36-37.
Hulme, Graham et al. The National Portrait Gallery: an architectural history. London: National Portrait Gallery, 2000. 93.
Seddon, John P.  A Visit to the Architectural Museum Written for Students. London: The Royal Architectural Museum, 1884. 
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Map of Northwest London, 1862