Systems engineering approach in residential land planning

Residential land planning, which is concerned with the physical development of land for residential use, is a multidisciplinary activity wherein the physical planner, engineer and architect play very prominent roles. Cost is paramount for low-income households. Therefore, in residential land planning for producing lots for this economic group, all possible efforts have to be made for reducing the cost per lot consistent with acceptable standards. To achieve this objective, residential land planning should be concerned not only with physical planning but should also take into account the interaction between the spatial design, the architectural design of the dwelling and the design and layout of utility systems so that the cost per lot including the service connection cost is minimised. In the paper, the systems nature of the residential land planning problem has been discussed and a cost-optimisation model for obtaining the optimum physical design of a planning module (a unit of design) fulfilling the given constraints has been developed using the technique of geometric programming. Application of the model is illustrated with a number of example problems using the field data, which show large cost differences from one system solution to another. This establishes the need for such an approach if cost reduction is the primary objective. The geometric programming technique of optimisation adopted in the paper could be used by a designer in the smallest design office with the help of a low-cost programmable calculator and the programmes developed by the author.