United States The American Housing Survey is conducted by the United States Department of Housing and Urban Development (HUD) every two years. A 2007 literature review conducted for HUD's Office of Policy Development and Research found that the most commonly used measures of overcrowding are persons-per-room or persons-per-bedroom. The United States uses persons per room, and considers a household crowded if there is more than one person per room, and severely crowded if more than 1.5 persons share a room.
World Health Organization The
World Health Organization is concerned with overcrowding of sleeping accommodation primarily as a risk for the spread of
tuberculosis and has attempted to develop measurement indicators.
United Kingdom The
Housing Act 1985 states: "The room standard is contravened when the number of persons sleeping in a dwelling and the number of rooms available as sleeping accommodation is such that two persons of opposite sex who are not living together as husband and wife must sleep in the same room. For this purpose, children under the age of ten shall be left out of account, and a room is available as sleeping accommodation if it is of a type normally used in the locality either as a bedroom or as a living room." The Housing Act describes how many persons are permitted per room, as well as amount of floor space per room as outlined in the table below. Children under 1 year are not counted, and children between 1 and 10 years are counted as half a unit.
European Union Eurostat uses a stricter definition of overcrowding, known as 'the Bedroom Standard'. An overcrowded household is defined as one which has fewer rooms than the sum of: • one room for the household; • one room per couple in the household; • one room for each single person aged 18 or more; • one room per pair of single people of the same gender between 12 and 17 years of age; • one room for each single person between 12 and 17 years of age and not included in the previous category; • one room per pair of children under 12 years of age. For example, a household of a single person living alone is considered overcrowded unless he or she has a living room which is separate from the bedroom (points 1 and 3 apply). However, while the Bedroom Standard is generally advocated by policy advocates, statutory space and occupancy standards are usually either less generous, partial (for instance they apply to social housing only) or non-existent. According to Eurostat, in 2011, 17.1% of EU population lived in overcrowded households by the above definition, with the number varying strongly between countries: the overcrowding rate stood at 43.1% in 12 newest member states compared to only 10.1% in 15 oldest members. Lifecycle has remained a powerful determinant of overcrowding. Eastern Europeans aged under 18 are on average 2.5 times more likely to experience overcrowding than those aged over 65. Affordability problems of young adults, who had to delay home leaving, contributed to unrelenting overcrowding, but so did the legacy of a housing stock composed of many small dwellings.
Sweden Swedish statistics and politics have used three different definitions over the years: The most dramatic change took place according to "norm 2" between 1960 and 1975 because of the
Million Programme. Of the households that are regarded as overcrowded according to "norm 3", two thirds are single persons living in 1-room apartments without a separate living room. ==Risks due to overcrowding==