Thermal performance of naturally ventilated test building with pitch and ceiling insulation

A field study was carried out to evaluate the benefits of insulated roof and insulated ceiling for naturally ventilated buildings in Malaysia. Two identical test cells with dimensions of 4m × 4m × 3m were used as building samples. Both test cells have identical design and were constructed with conventional building envelope. The non-insulated control unit is named as Test Cell A (TCA) while the insulated test unit is named as Test Cell B (TCB). Conductive thermal insulation of R-value 2.22 (m2K/W) and 2.88 (m2K/W) was consecutively installed at the roof pitch and internal ceiling respectively. For each insulation configuration, the outdoor and indoor environmental data for both test cells were concurrently monitored using automated data logging equipments. Data logging duration was five days for roof pitch insulation and ten days for ceiling insulation. This paper presents the findings on thermal impact on the non-insulated Test Cell A and insulated Test Cell B. These are appraised by the respective indoor temperature. The finding shows that pitch insulation and ceiling insulation lower the daytime indoor temperature up to 0.8°C and 0.6°C respectively. However, both have adverse impact at night. It is concluded that both pitch and ceiling insulations are beneficial to reduce the day-time thermal impact. The impact is more significant with the pitch insulation. Due to the nominal temperature differential to determine the benefits on the thermal comfort conditions, a cooling load analyses could further substantiate the advantage and disadvantage of the insulation.