The diploma thesis deals with the analysis of the use of natural thermal insulation in structural elements of modern wooden buildings, which meets the highest demands from aesthetic, functional, energetic and environmental point of view. The aim of this work was to create a comprehensive picture of thermo-insulating, sound-insulating and fire-resistant properties of thermal insulation materials based on wood and hemp fibers. The aim of the work was to carry out a mid-dimensional fire resistance test of two samples of the structure of the perimeter wall of the wooden building, which differed in the material of the thermal insulation layer. One sample had hemp thermal insulation and the other had a fiberboard thermal insulation. The model fire resistance test was performed using a radiant heat source, which was a ceramic radiation panel with a max. power of 50.5kW/m2. In addition to gathering knowledge about the fire resistance of particular structural elements, the intention was also to design a model that meets strict energy performance requirements for buildings and also serves to build eco-friendly buildings from renewable sources. The result of the work is the evaluation and comparison of the behavior of the samples in the conditions of the model fire and the determination of their anticipated fire resistance. From the tested samples, the sample with fibreboard insulation better resisted by fire.