Sustainability assessment model for mass housing's interior rehabilitation and its validation to Ekbatan, Iran

Abstract

Mass housing (MH) buildings from the ‘60s to the ‘80s, after decades of continuous use and inadequate maintenance, cause several sustainability issues and need rehabilitation. Most current conventional rehabilitation approaches have long been criticized because they consider neither sustainability requirements nor contemporary building standards. In this regard, the assessment and selection of suitable approaches for rehabilitating MH interiors, from a holistic sustainability viewpoint, is a crucial issue that faces several challenges since this is a multidisciplinary and multi-criteria process. On this subject, the present study develops a novel MCDM model based on the MIVES and Delphi methods for the holistic sustainability assessment of MHs’ interior rehabilitation considering involved stakeholders' preferences. This MIVES-Delphi model relies on a comprehensive literature review, experts' seminars, on-site surveying, LCA, BIM, user/expert-based questionnaires, bias reduction, and sensitivity analysis. The model was first applied in the Ekbatan MH case study, the largest MH in Iran, to assess the sustainability of four different interior rehabilitation scenarios, including three common rehabilitation scenarios plus an innovative one. Consequently, the new model was validated, and the most sustainable scenario was selected. The specific results regarding these scenarios' evaluation disclosed that none of the common rehabilitation scenarios could either meet the minimum sustainability target value or serve as proper solutions for MH's interior rehabilitation. Contrarily, the fourth scenario, with a global sustainability index of 0.71, could meet the standard minimum target. This outcome provides a possibility for innovative rehabilitation processes to have positive effects on increasing the sustainability performance in MH buildings.