Decision-making model for the evaluation of industrialized housing systems in Ethiopia

Abstract

Purpose The industrialized housing system (IHS) is regarded as an effective building philosophy based on off-site construction techniques to achieve rapid and cost-effective housing development. The purpose of this paper is to develop a multi-criteria decision-making support system (DMSS) model for the evaluation of housing systems to select the relevant decision factors and to identify the types and characteristics of suitable IHSs for application in a mass housing development. Design/methodology/approach A multi-criteria DMSS model with the analytical hierarchy process was designed. Based on the literature review and also the response of the ten experts’ interviews, 30 decision factors were identified for evaluation. In addition, 5 IHSs were considered as a case study for testing the model. Then, 30 professionals participated in a questionnaire survey conducted to evaluate the priority vector importance level of the decision factors and housing systems. Findings The result of the decision-making process showed that the top three decision factors are customer needs, supply chain and the construction industry. In addition, both precast concrete beam and slab blocks, as well as agro stone panels are identified as suitable housing systems. The systems have the characteristics of being lightweight, easy to produce and erect, and cost-effective, and they use local input resources and semi-skilled labor. The findings also revealed the potential and practicality of the model among multiple alternatives across multiple decision factors. Research limitations/implications The study has faced the limitations of available professionals and experts who have rich experience in the application of IHSs. In addition, there were few types of alternative IHSs and limited practice of IHSs implementation in large-scale housing construction. These challenges caused limitations to the relevant data collection. In order to address these challenges, all the available experts from the different sectors of the construction industry with the experience of IHSs construction are invited to participate and the available alternative IHSs in the market are selected for evaluation. Practical implications The rational evaluation method used to determine the important decision factors and the general characteristics of the suitable housing systems can help housing developers and decision makers in developing countries to make informed and effective decisions. Social implications The findings of the study help to address the challenge of lack of sufficient housing supply to the overwhelming housing demand that exists and identify the most important decision factors and suitable housing systems that can be applied for the rapid and decent large-scale housing developments at an affordable price. Originality/value This paper bridges the knowledge gaps that exist regarding the identification and evaluation of IHSs in Ethiopia. This study can help practitioners, housing developers, and decision makers to make informed and effective decisions regarding the evaluation and selection of IHSs.