A METHOD FOR EVALUATING THE FLEXIBILITY OF FLOOR PLANS IN MULTI-STORY HOUSING
An attempt is made to develop an approach to flexibility in housing design, which would be applied in both academic studios and in practice. This approach is based upon the concept of interdependence of the factors and the variables of design encountered in the process of building flexible housing.
In multi-story housing there is a need for designing flexible plans which would be able to meet uncertain requirements of people. Although a number of proposals for flexible housing have been presented offering different degrees of flexibility focusing upon different design factors, the issue of flexibility has not been adequately solved. This is mainly because there is confusion as to the meaning of flexibility. Three types of flexibility exist in multi-story housing; elasticity, adaptability and versatility. This study is concerned with the last two only.
The process of designing for flexibility must be examined from both the architect's point of view and the user's point of view. In any housing design the architect and at times the user deals with five scales of flexibility: room, dwelling unit, building, clustering the buildings in the site, and community. This study focuses upon the dwelling unit and building flexibility.
Degrees of flexible space suggested in the proposed solutions range from an absolute flexible space without restriction, to one with a limited degree of flexibility and finally to one with too many limitations. Neither extreme leads to a successful solution. Overemphasis on a single design factor invariably results in a less successful solution, than one based upon a number of interdependent factors.
The study develops a method of evaluation (in which varied subjective values may be inserted) in order to judge the degree of flexibility of floor plans in multi-story housing. Based upon evaluations alternate plans, design criteria are established.
The scales of flexibility which will be analyzed, are the dwelling unit and the building flexibility. The factors of design studied at both scales are the housing forms, building structure, circulation, and technical service positions which are the factors that most affect the building's flexibility. Similarly, the unit type, size, proportion, technical service positions and building structure are the factors that most affect the dwelling unit flexibility.
A variety of plan solutions result from the different combinations of design variables of each factor mentioned above. Each plan is evaluated on the basis of nine design goals, and is given a quantitative merit value, which indicates how effectively this plan satisfies these design goals.
The next step calculates the average score and the relative weighting score of each design variable. In the last step the performance index of flexibility for both building and dwelling unit is computed and the optimal set of plan solutions are determined.
From the examination of the most important characteristics of these optimal plan solutions, criteria of flexible multi-story housing are established. These criteria are: compacting the services of building or a dwelling unit to free the remaining space; locating the external and internal services of a building in proximity to one another; choosing the proportion of dwelling unit and selecting the position of wet function, which both most effectively allows for adequate flexible space; and considering the structural limitations in such a design.
The method of evaluation is itself flexible enough to be used for evaluating the flexibility of other building types. The study tries to present a workable guide to these combinations of design variable, which provide flexible space while avoiding crippling limitations.