Effect of foundation designs of passive house on the thermal bridges at the ground

Purpose This paper aims to understand the effect of different foundation designs of passive house on the resultant thermal bridges, at the junction between a wall and a slab on grade. Design/methodology/approach The linear thermal transmittances of some newly developed foundations of passive house are determined. The investigated foundation designs are L-element, U-element and foundation with foam glass technique. Findings It is found that the special design of passive house foundation can considerably influence the heat flow through thermal bridges. In this context, it is proposed a new foundation design of passive house, which has relatively low heat loss through thermal bridges. The results are compared with the “default” ISO values used to evaluate the effect of thermal bridges in typical buildings. It is found that there is large difference between the calculated linear thermal transmittances at the investigated foundations of passive house as compared to typical buildings. Practical implications The results can hopefully be used to improve the energy efficiency of the passive house. Social implications Sustainable solution of buildings. Originality/value A new foundation design of passive house is suggested to reduce heat loss through thermal bridges.