Multi-criteria selection of high-performance glazing systems: A case study of an office building in New Cairo, Egypt

Abstract

The energy consumption of fully glazed office buildings is very high due to the heavy cooling loads in summer. Therefore, building designers resort to the High-Performance Glazing System (HPGS) solutions to reduce solar heat gain and save energy. However, the selection of most sustainable HPGS is considered a complicated process because the one criterion decision method - which building designers still tend to use - cannot solve this complexity. Multi-Criteria Decision Making (MCDM) analysis can solve this problem and rank the alternatives. In this paper, the Analytic Hierarchy Process (AHP) - one of the MCDM methods - is applied by SuperDecisions software to rank three proposed HPGS alternatives for an existing office building in New Cairo, Egypt as a case study in a hot desert climate zone. Four criteria of sustainability (energy, environmental impacts, cost, and occupant comfort) are assessed and a new weighting method is applied based on LEED rating system to prioritize the alternatives. The ranking results show in the first place the Photovoltaic glazing system followed by the Low-E and Electrochromic glazing systems, respectively with a negligible difference. The Life cycle cost criterion is the major influencer on the ranking results according to the applied sensitivity analysis.