Pre-regulation terraced houses in the United Kingdom

A pre-regulation terraced house is a type of dwelling constructed before 1875 Public Health Act. It is a type of British terraced house at the opposite end of the social scale from the aristocratic townhouse, built as cheap accommodation for the urban poor of the Industrial Revolution. The term usually refers to houses built in the century before the 1875 Act, which imposed a duty on local authorities to regulate housing by the use of byelaws. Subsequently, all byelaw terraced housing was required to meet minimum standards of build quality, ventilation, sanitation and population density. Almost all pre-regulation terraced housing has been demolished through successive waves of slum clearance.

Between 1801 and 1901 the population increased fourfold, and during this period there was a migration from the land into towns (urbanisation), as the nature of work changed with the Industrial Revolution. Urban population increased tenfold, and there was a need to build houses for the urban worker. Employers built rows of back-to-back and through houses (i.e. those with front and back doors) on the ground available. In older towns they were constrained by the mediaeval street patterns and the need to fit as many houses as possible on the traditional long plots. The poorest lived in single-roomed houses facing onto a communal courtyard with a shared outhouse (privy), a cesspit, a standpipe, and consequently high rates of infant mortality, typhus and cholera.

The urban population influx started in around 1820 as steam or water power was successfully harnessed to drive the machines, and to produce the iron and steel to build the machines. More workers were attracted in from the countryside to tend the machines and a large number of dwellings were required in short order. Water powered mills were built next to rivers and the housing next to the mills in the floodable low-lying ground. The particles from smoke from the steam engines' boilers descended and wrapped the adjacent housing in a layer of grime. The workers were unskilled and poor, so could pay little rent. Although their families were large, they squeezed in lodgers.

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