The Influence of Thermal Resistance and Thermal Mass On the Seasonal Performance of Walling Systems in Australia

This paper describes an experimental investigation of the thermal performance of four Australian domestic walling systems (cavity brick, insulated cavity brick, insulated brick veneer and insulated reverse brick veneer) having various combinations of thermal insulation and of thermal mass location within the wall. This experimental analysis extends further the previous studies of the benefits of thermal mass on the overall thermal performance of building enclosures (Gregory et al. 2008, Luo at al. 2008, Alashaary et al. 2009). The comparison is based on the time required to maintain thermal comfort for free-floating internal conditions. The results clearly show that internal comfort levels are influenced by both the thermal resistance of the walls as well as the extent and location of the thermal mass, with neither parameter being the sole predictor. The best thermal performance is therefore obtained by an appropriate combination of thermal mass and resistance, rather than focussing on the overall wall thermal resistance (R-value) alone. A new approach of density temperature plots for comparison of temperature variation is also used in the assessment of module thermal performance.