The aim of the thesis is to verify thermal performance of the selected log structures with natural insulation. Furthermore, the thesis deals with theoretical and experimental verifying of moisture content of given log structures during monitored winter period. Timber structures, thermal insulations of timber structures and actual requirements for thermal performance of structures and components in accordance with the standard STN 73 0540-2: 2016 are described in the thesis as well. The result of the thesis is final assessment of measured data and subsequent proposals for practice.