Study of heat flow through a rammed earth wall building

In 1999, a 2100 m2 (GFA) two-storey rammed earth building was built on the Thurgoona campus of Charles Sturt University. The climate at Thurgoona is considered Mediterranean – hot dry summers and cool winters. The internal and external walls of the building are constructed from 300-mm thick rammed earth (pise) and are load bearing. The thermal performance of the building has been investigated, both experimentally and theoretically over the summer and winter seasons of 2000/1. As part of these investigations heat flux sensors and thermistors were embedded in one of the external walls of a ground floor office, and data from the transducers has been used to determine the heat flow at the internal and external wall surfaces. The simulation software, TRNSYS, has been used to model the thermal performance of the same office. The programme allows the user to calculate the heat flow at the walls, which define any particular thermal zone. A comparison of measured and predicted values of heat flows and air temperatures has been used to validate the model. The model has then been used to simulate the effect of shading and added insulation on the thermal performance of the external walls in both summer and winter and these results are also presented in this paper.