Projections of population composition for the next 30 years show that in many developed countries, one in five persons (in some cases, one in four) will be elderly and that the trend will only be delayed in developing countries. In the UK alone there are (1996) about 4.25 million adults and 100,000 children with mobility impairment. All suffer disadvantage because of inappropriate or inaccessible housing, disadvantage which usually extends to everyone involved in their lives -- other members of their family, friends and carers.
In the past, housing for elderly and disabled people was considered special-housing, requiring design that distinguished these units from housing stock in the general market. This market segmentation has been rejected for many reasons. Specially-designed housing was expensive and could not be afforded by elderly and disabled people, who tend to have lower-than-average incomes because of lower or non-participation in the labour market. As a consequence, many units of housing for elderly and disabled people were built by governments using public funds and offered to tenants at subsidized rents. In many countries, governments are withdrawing from such investments due to government reform reductions in public expenditures or increasing use of the market. Regulations and bureaucracies that managed access to such housing are now considered wasteful. Special housing also isolated elderly and disabled persons from mainstream social, economic and cultural activities. Under human-rights requirements, these groups cannot be relegated to housing of low quality or space standards, nor can they be excluded from participation as citizens. Consumers have also tended to reject special solutions.
In countries where new housing is still being constructed, universally-designed housing reduces expenditures for housing over the long term while increasing the usefulness of the housing stock. In fact, the costs of not providing universal housing are now beginning to exceed the costs of providing specially-designed housing in economic, environmental, social and moral terms. The cost of building and operating a limited and special barrier-free stock through government subsidies outside the housing market may no longer be feasible. It is clear that retrofitting housing is not cost-effective; it is wiser to building housing that is universally designed in the first place. The greatest change required is philosophical rather than technical or economic. The Joseph Rowntree Foundation in the UK has been exploring the design and cost implications of these adaptable homes, and is intending to build them to see how their cost and popularity compare with adjacent new property.