Experimental investigation of cooling potential of a ventilated cool roof with air gap as a thermal barrier

In arid regions, global warming raises indoor air temperatures and consequently energy demand. Innovative cool roofing systems has to be developed to reduce indoor air temperatures and hence building energy consumption. The current study examines the advantages of using polystyrene foam insulation with a radiation reflector as a cool roof in Omani summers, as well as the thermal barrier effect of air circulation between them. The ventilated cool room has lower indoor air and heat flux values than the normal reference roof in field tests. The heat flux through the cool roof was reduced by 14 W/m 2 , 23 W/m 2 , and 29 W/m 2 when the ventilation between the PsF insulation and the radiation reflector roof was 0, 25 cm, or 50 cm, respectively. The roof’s thermal resistance increased due to the ventilation system’s dynamic air flow between the PsF insulation and the radiation reflector (enhanced convective heat flux). During hot sunny days, the experimental studies demonstrated that the ventilated PsF insulation-radiation reflector cool roof lowers the temperature of the interior by a substantial amount and decreases heat flux through the roof.