The McKay housing subdivision is ofhistorical and social significance as the first stage of the suburb created by Australia's leading industrialist and a milestone in the development of the industrial suburb, under the influence of the model worker's towns and Garden City movement. Sunshine became a yardstick for planning and housing reformers, with H.V. McKay being regarded as an expert on planned industrial housing. The McKay estate is ofarchitectural significance as it marks a crucial phase in the development of Sunshine, housing the resident work force which promoted further industrial development.
The estate is also of historical significance in relation to H. V. McKay's important role in the history of industrial relations in Victoria and Australia, as the provision of housing for his workers was one of the arguments made by McKay in defending the Basic Wages Case which lead to Justice Higgins' "Harvester Judgement". It is also historically significant for is associations with the dozens of employees of the Harvester Factory who built and resided in the houses.
The group of houses along Forrest Street, Ridley Street, Sydney Street, King Edward Avenue, and Kororoit Street, represent the type of houses built either by or for company employees, foremen and managers. The houses include major remnants of the large blocks allotted to senior staff of the Sunshine Harvester Works. Most of the houses were set back on their blocks with side drives, rather than rear service lanes, giving an air of spaciousness and permitting large gardens (of which some remnants survive).