The character of local new housing began to change after 1851, with westward expansion along roads parallel with the railway and at the western end around Abbey Road and its side-roads.

The east-west roads were Boundary Road and Belsize Road, where 41 houses were built in 1851-2, some by Robert Yeo.

Close-packed middle-class housing in Belsize Road was virtually complete by 1866, though in 1871-2 five more houses were built. Belsize Road was occupied by ’skilled workers and similar’.

The estate shared in the flat-building of the 1930s decade. The first major project was the building of 14 blocks by A. Clarke on the south side of Belsize Road from 1932 to 1936.

There was extensive rebuilding after 1945, mostly for local authority housing. The whole area suffered war damage and houses were dilapidated through tenementation and neglect. About 1955 the Communist party described the Belsize Road area as overcrowded, with damp and crumbling houses; there were said to be 2,372 people in 369 houses.

During the same period a large council estate was built on the west side of Finchley Road, stretching from Boundary Road northward to Belsize Road and centred on Hilgrove Road from which it took its name.

Later phases, by the borough architect S. A. G. Cook, dated from 1970 and 1973 and included a multi-storeyed car park, shops, a community centre, and health centre in Belsize Road. Other recent construction has been of pastiche Georgian or Victorian houses in Fairfax Road and the eastern part of Belsize Road and in Hilgrove Road and of striking blocks of flats and offices.

Some of the mid-19th century houses remained, mainly on the better built eastern side of the estate, including most of the north side of Belsize Road.