Substandard housing is associated with an absence of public sanitation measures such as: clean, uninfected drinking water; human waste disposal; and garbage removal. It is also associated with communities which have inadequate medical, educational and other services. Substandard housing units are often stations on the way in and out of houselessness. Their inhabitants are often characterized by an insecure economic situation. An indicator of the sub-standard housing problem is that demand for accommodation in government-sponsored council houses and low-income-family apartment developments exceeds supply.
Even in the more developed countries, housing stocks contain large numbers of dwellings that are unfit and even not repairable. In the developing countries, corresponding to the distribution of incomes, a certain duality has come to characterize the major urban areas: the city proper is often barely distinguishable from its counterparts in the high-income countries, while alongside it and linked to it in the economic nexus are the barricados, bustees, bidonvilles, favelas and shanty towns that house what has become known as the marginal or transitional population.
In the UK, for example, nearly 20% of the housing stock is classified as unfit or in an unsatisfactory condition. Government statistics show that over 3.8 million dwellings require expenditure totalling £18.84 billion at an average cost of £4,900 per dwelling. Twenty percent of all primary schools are house unmodernized buildings which are over 80 years old. A quarter of all schools also have outdoor lavatories and one in 10 children are taught in temporary accommodation.