Thermal bridge occurrence in straw-bale timber frame walls

Timber frame walls usually require additional filling that improves their thermal insulation. Straw bales, which constitute a waste product from cereals, are a sustainable solution employed for that purpose. The temperature distribution in a wall is influenced by the heterogeneity of the partition that comprises the elements characterised by higher thermal conductivity, i.e. timber frame. Thermal bridges (i.e. thermally weaker areas) in walls are conducive to the mould growth as well as condensation; thus, it is important to take these phenomena into account at the wall designing stage. The work describes a 2D heat-transfer analysis carried out with the finite element method by means of THERM software. The analysis involved several different variants of external walls and corners. The thermal parameters of the investigated straw were derived from our former research. The obtained results were shown as the values of thermal transmittance coefficient and linear thermal transmittance equivalent to timber construction. The temperature distribution for the investigated wall was presented in a graphical form. The study also involved examining the possibility of surface condensation. (paper)