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Report of the Second International Expert Seminar
on Building Non-Handicapping Environments:
Renewal of Inner Cities

Prague, October 15-17, 1987

Download the Prague proceedings as a PDF file (420 KB)

Development of Design Guidelines of Dwellings for An Aging Society:
A Japanese Perspective

Satoshi Kose, Michico Nakaohji, Eiichi Itoigawa and Tomonari Yashiro,
Building Research Institute, Japan
Toru Takahashi, University of Tokyo, Japan


The Japanese society is aging at an amazing speed. Within only 25 years, the percentage of people 65 and over in the total population will increase from 7% in 1970 to 14%, whereas in other countries this is taking 50 years or longer. It is most important to provide a residential environment adapted to the aged population including housing designed to meet the preferences of old persons and their requirements which grow as their functional abilities decrease.

"Design Guidelines of Dwellings for An Aging Society," presented here, is a summary of various guidebooks on housing for an aging society which have been published in Japan. The guidelines are intended to present both a general policy and detailed design features for dwelling units and equipment. It is hoped that they will be used by local governments in promoting appropriate housing development measures, both public and private.

Aging Trends and Housing Conditions

The National Census Survey in 1985 showed that there are 12.4 million people 65 or older in Japan, 10.2% of the population. Estimates by the National Population Institute of the Ministry of Health and Welfare suggest that old people will be more than 23% of the total population by 2025. It is also estimated that at that time the group 75 or older will be larger than the group between 65 and 74.

The trend toward an older population differs from region to region in Japan. In general, it shows earlier in the country and spreads to the larger cities. Along with population structure, family structure is also changing rapidly. Households are rapidly becoming smaller. At present, about 70% of the elderly live with younger relatives, but in 2025 about 50% of the elderly will live independently.

In general, old persons tend to have their own houses. This is less prevalent in cities, however, where houses are also smaller. Household size seems to affect housing conditions as well. Multi-generation families, i.e. old persons living with their children and grandchildren, tend to live in their own houses, while independent old persons tend to live in privately-owned rental housing. Those living in rented housing move frequently. Very few houses are designed and built for use by old persons who thus encounter various inconveniences in their day-to-day living.

The Concept of Housing for Old Persons

In an aged society, old people are not special. To eliminate difficulties for them, residential environments should be designed with the concept of normalization. What we here term housing for old persons is housing designed to fit an aged society. It is built to assist old persons with reduced physical and mental abilities, to be adjustable to different forms of living, and to be easily adapted as needs for equipment and facilities increase. Adaptation should be both easy and economically feasible.

Supply and Demand for Housing for Old Persons

Estimates of housing needs for the aged society suggest that in the year 2020 there will be more than 18 million households with one or more senior citizens, and that more than 9 million new dwelling units will be needed over the next 35 years to cover this increase - 260,000 per year. This is a large increase in comparison to the previous estimate of a total 1.2 to 1.3 million new housing units per year. It will be quite difficult to provide housing for all old persons through new construction alone, and renovation of existing housing stock is quite important. In promoting such a housing supply, publicly constructed rental housing, Housing and Urban Development Corporation and Housing Loan Corporation (HLC) supported housing will play an important role. In addition, private residential construction will have to be actively guided by the government if it is to be adapted to an aged society.

Typology of Housing for Old People

In the following, several basic requirements for housing for old people are categorized. What matters here is physical condition, family conditions and social conditions.

Physical Condition

The degree of functional impairment due to aging can be represented in several ways. If daily activities are taken as a measure, the abilities of old persons can be divided into 9 levels grouped into three categories: healthy and independent; partially dependent; and dependent, as shown in Fig.1. Respective care needs are shown in Fig. 2. Regarding care needs it would seem that most of the old people are partially dependent or dependent, but in reality more than 90% are independent. They may become partially impaired, but they die before they become severely dependent.

Fig. 1. Degree of Functional Impairment and Daily Activity Area

I Physically independent
1 Full utilization of transport facilities
2 Partial utilization of transport facilities, walking distance maintained, sometimes enlarged
3 Only selective use of transport facilities, walking distance shortened
4 Transport facilities almost abandoned, walking distance further shortened
5 Daily activity area almost limited to dwellings incl. garden but living independently

II Partially physically dependent
6 Daily activity area within house, meals in one’s own room, almost independent, mobility within house partially impaired

III Physically dependent
7 Personal hygiene with assistance
8 Personal hygiene in own room, bathing frequency greatly reduced, intensive assistance
9 Almost bed-bound

Fig. 2. Degree of Functional Impairment and Care Needs

Levels 1 2 3 4 5 6 7 8 9

- no special care needed -
- residential care on call
- personal care
- nursing care
- medical care

Family Conditions

Whether old persons live with family members who can assist them in their daily lives, and whether they are economically independent, will determine their requirements for social services and housing. Multi-generation families and single or married old people who need public housing come under the subject of direct public housing measures.

Social Conditions

From the social point of view, three levels of measures are desirable: support for independent old persons; support for semi-dependent old persons; and support for dependent old persons. Existing measures in Japan can be categorized as shown in Fig. 3.

Fig. 3. Existing Social Measures for Old Persons in Japan

Levels 1 2 3 4 5 6 7 8 9

Living with - pension
the family - National Health Service

- public housing policy
Loan through HLC
HUDC Housing
public rental housing

Day centers
Visiting day services
Care for confused persons
Old persons only
- pension
- National Health Service

Public rental housing
Nursing home
Special nursing home

Housing Systems

Existing housing solutions for old persons can be classified as either ordinary or institutional housing. The trend is toward ordinary housing, because institutionalization requires extensive resources of money and manpower. For ordinary housing, measures for services on call, physical standards of remodeling, and transportation systems are needed. To realize these, adaptable housing must be available. Special housing for old persons with residential care service is now being developed in Japan. It is called the "Silver Housing Plan" and demand is expected to be very high. This is the first attempt of the two government departments, the Ministry of Health and Welfare and the Ministry of Construction, in a joint policy for our aging society.

Basic Requirements of Dwellings for An Aging Society

Table 1 lists some basic requirements to be considered in buildings for odl persons with various degrees of functional impairment.

Table 1. Basic Requirements of Housing for Old Persons
Levels Daily Activity Requirements

Physically independent
1 public transportation environment conducive to social participation
safety in traffic and street environment

2 walking + public
transportation domestic safety

3 walking distance easy vertical movement

4 short walking distances easy horizontal movement without unnecessary height differences

5 in and around
dwellings comfort, functionality

Partially physically dependent
6 inside dwellings ease of operation, evacuation safety

Physically dependent
7 inside dwellings,
assistance needs residential care

8 extensive assistance
needs personal care

9 almost bed-bound nursing care

Independent Old Persons

It is necessary to provide a secure environment for independent living. Since the functional ability of these old persons is expected to deteriorate with time, site selection, traffic safety and a safe outdoor environment should be given careful consideration. At later stages their mobility will become more restricted, and stairs and steps can become barriers.

Semi-Dependent Old Persons

Most daily activities will be carried out at home, and careful planning and detailed design are necessary. The house should be comfortable, equipment should be easy to operate, and there should be safe means of evacuation in case of emergency.

Dependent Old Persons

Houses should be designed to facilitate care services at various levels. It will sometimes be difficult to introduce into ordinary houses new equipment for special needs -- horizontal lifts, for example.

Housing for Old Persons and Care Services

Old persons who need constant care will occupy an entire room, even though they might not be confined to bed. The room will be exclusively for their use, and may have to be larger than usual and located in the house with special consideration given to circulation patterns. It may be necessary to introduce additional equipment. Appropriate siting of special housing for old persons and the relationship between rooms and staff offices should also be considered.

As shown above, the housing requirements of old persons change as their degree of impairment increases. It is therefore desirable to draw up several kinds of design guidelines. Problems related to construction methods must be solved in order to adapt existing dwelling units for use by old people. Further research in this area is needed. The "Project on the Improvement of Residential Environment for the Aging Society," which is to run for five years starting in 1987, may make valuable contributions here.

Design Guidelines for Dwellings for An Aging Society

If old persons are to fully enjoy a good residential environment, the following aspects have to be considered: site planning, communal facility planning, block planning, and housing unit design. Of these, dwelling unit design has been studied most intensively, and the result is presented here.

The points to be considered in housing for old persons are basically similar to those for ordinary housing. Safety should be given more emphasis, however, because old persons are more vulnerable to accident injuries. Two checklists have been compiled on basic requirements common to buildings and housing units and specific points to be considered in rooms and spaces within flats.

In principle, the guidelines are meant for elderly people who are nearly independent in their daily activities within their dwelling. They may be functionally impaired to some extent (at stage 6, or partially at stage 7), but they require little assistance from others. Here follow some comments on the guidelines, starting with an explanation of the concept.

Basic requirements for the design of houses:

Safety, function, comfort and economy must be considered

Adaptability with increasing age must be considered. The design should be acceptable to both old and younger occupants.

A special room should be designated for old persons, if the size of the house permits.

Room Layout

Room layout can be varied according to the composition of the family. If the house contains family members other than old persons, the priority of the room or space used by the old person should be considered, and should be planned to avoid inconvenience to all family members. Special attention should be given to the possibility to adapt to changing needs as the old person grows older. Additional equipment may be necessary and extra space may be needed for intensive care service.

Entrance and Exit

The type of door selected and the way the sill is designed are important. Safety and ease of use are basic points. A sliding door may be a good solution, as it does not get in the user’s way, but the threshold must be level with the adjacent floor. Wheelchair use should be taken into account. The door should be wide enough, and there should be provision for storing an outdoor wheelchair. The Japanese do not wear shoes indoors, and a wheelchair for indoor use is different from one for outdoor use -- many old persons only use a wheelchair outdoors.

Corridors and Circulation

If wheelchair use is anticipated, it should be remembered that existing chairs require a minimum clearance of 80 cm (though a smaller chair might be suitable for indoor use). Old people with functional impairment of their upper extremities may not be able to use a manual wheelchair. If they can use one, they can perhaps also manage to move about in the house using only handrails.


Existing stairs are too steep for old persons. The steps should be wider, and their rise lower. Handrails are a necessity.

Floor Treatment

Falls on level ground are one of the most important causes of accidental death in Japanese homes. Tripping and slipping should be avoided by careful planning and selection of materials. Small differences in level (such as door sills) should be avoided. Floor material should be chosen to soften the impact of a fall.

Room Environment Natural lighting and ventilation are important. Mechanical and electrical equipment should be only supplementary. An emergency exit should be available.

Living Room The living room and other rooms for common use should be designed so that family members do not disturb each other. Good circulation patterns are important in planning. It is often a sensible solution to provide a direct exit from the old person’s room by way of the garden.

Sanitary Facilities

Differences in floor height between bathroom, toilet and corridor -- including door sills -- should be eliminated to avoid the danger of tripping. The risk for slipping should be minimized. Sharp corners and other features that increase the danger of a fall should be avoided. Handrails should be provided. The Japanese are accustomed to immersing themselves in a tub of warm water. To make bathing easier, the height of the tub needs to be reconsidered. Fixtures should be safe and easy to operate -- the lever type is advisable. The toilet should be equipped with handrails (both horizontal and vertical).


The kitchen should be designed to minimize the risk for burns or scalds. Electrical cooking appliances, perhaps microwave ovens, are good choices. The height of the kitchen cabinets and workspaces should be considered if the kitchen has multiple users.

Reception and Recreation Spaces

Visitors are very important for old people. The dwelling should be designed so that visitors may easily be invited inside without disrupting the rest of the family. Watching TV is a common activity, and since old people tend to be hard of hearing earphones or a hearing aid can be provided. The old person’s room should have good sound insulation, so others will not be disturbed. The room should also have easy and private access to the outside.


Housing designed for old persons should be planned for easy adaptation as they grow older and their condition deteriorates. It will seldom be necessary to introduce a horizontal transfer lift, however, and it may not be necessary to prepare every house for such a measure. But some sort of remodeling should be taken into consideration. Some equipment may require structural reinforcement of floors or walls.


Houses and equipment need maintenance. Careful attention must be given to design, so that maintenance is easy and economical. Ease of daily cleaning should also be considered.

Introduction of Advanced Technology

Some products of advanced technology, such as electronic monitoring or surveillance devices, are sure to be introduced into old persons’ homes.

Concluding Remarks

To put these guidelines into practice, central and local governments must take measures to see that they are implemented. Some of the recommendations have already been communicated to local governments in form of a memorandum. The memorandum guarantees partial financial support from the central government for specific renovations of existing public rental housing. Other measures are still under consideration and will be introduced in due course. The Development Project mentioned earlier is also expected to contribute to progress in this area.

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