 In 1950 the boundaries of the seat were left unchanged, but it was reclassified as a borough constituency.In 1965 Brentford and Chiswick became part of the London Borough of Hounslow and Greater London.The seat rapidly became under-sized in electorate, see malapportionment – the area forming the seat was unusually declining in population, with in the 1918 to 1930 period the major loss of servants and lodgers among many of the larger houses particularly in Chiswick, and areas of reduction of overly dense housing in Brentford.