Passive cooling strategies in roof design to improve the residential building thermal performance in tropical region

Residential sector represents an important part, almost one-third of total Indonesian energy demand. The literature survey showed that the cooling and lighting systems are the largest energy consumers in this residential sector. The aim of the present paper is to evaluate the effectiveness of suitable passive cooling strategies on roof level to reduce the building energy demand on equatorial hot-humid climate region. The feedback of previous researchers have identified that the main influencing factors on building thermal comfort are the building roof design and ventilation system. In the present study, the effectiveness of three passive cooling techniques on roof level, cool roof coating, thermal insulation on ceiling and natural air ventilation on attic zone, is studied to improve thermal performance of Indonesian residential buildings. Results showed that the simultaneous implementation of these passive cooling techniques is able to significantly reduce the temperature overheating and thermal discomfort by 37.3% in tropical region.