Life Cycle Assessment of flat roof technologies for office buildings in Israel

The goal of the current study was to evaluate the environmental damage from three flat roof technologies typically used in Israel: (i) concrete, (ii) ribbed slab with concrete blocks, and (iii) ribbed slab with autoclaved aerated blocks. The roofs were evaluated using the Life Cycle Assessment (LCA) methodology. The Production and Construction (P and C), Operational Energy (OE), and Maintenance to Demolition (MtoD) stages were considered. The roofs were modeled based on an office building module located in the four climate zones of Israel, and the hierarchical ReCiPe2008 Life Cycle Impact Assessment (LCIA) method was applied. The percent difference of one, which is the default methodological option of ReCiPe2008, and an ANOVA of the six methodological options of ReCiPe2008 were used. The results revealed that (i) in a hot climate, the best roof technology can be selected by considering only the OE stage, whereas in a mild climate, both the OE and P and C stages must be considered; (ii) in a hot climate, the best roof technology is a concrete roof, but in a mild climate, the best options are ribbed slab roofs with concrete blocks and autoclaved aerated blocks; and (iii) the conjugation of ReCiPe2008 with a two-stage nested ANOVA is the appropriate approach to evaluate the differences in environmental damage in order to compare flat roof technologies.