Polymer and non-polymer admixtures for concrete roofs: Thermal and mechanical properties, energy saving and carbon emission mitigation prospective

Buildings are accountable for the enormous energy consumption in the world. Therefore, energy-efficient building materials are inevitable in modern construction practices to diminish global energy consumption. In this paper, three industrial wastes (fly ash, ground granulated blast-furnace slag, and silica fume), four other admixtures (bentonite, metakaolin, oyster shell, and zeolite), and two polymer admixtures (Styrene-butadiene rubber, styrene-acrylic ester) are considered for the concrete to explore their potential for air conditioning costsavings, carbon mitigations, and payback periods in buildings of hot-dry (Jodhpur, India) and cold climates (Thessaloniki, Greece). The mechanical and thermophysical properties were measured for admixture-based concretes. The results revealed that among all admixtures studied, styrene-acrylic ester concrete roof exhibi­ ted better thermal performance with adequate compressive strength (34 MPa). The best economic benefit of styrene acrylic ester concrete roof in hot-dry/cold climatic conditions leading to the highest total air conditioning cost-savings (1.01 $/m2/1.53 $/m2), highest life cycle saving costs (48.9/31.2 $/m2), highest carbon mitigation (19.26/7.53 kg of CO2/year), and acceptable payback periods (11.6/8.4 years). The results of this research help engineers and architects to select the best admixtures for the concrete in terms of mechanical strength, energy efficiency, and carbon emission mitigation potential.