. Our firm occupies with log-cabins made of transylvanian wood, by selling and setting them up. The present wooden-houses are made of walls with three-sized thicknesses: - the deposits/warehouses for gardening tools are made of 19 mm thick walls; - the weekend-houses are made of 28 mm thick walls; - the garages, respectively, the vacation-houses are made of 45 mm thick walls. The 45 mm thick-walled wooden houses have double notches or fixtures, thus, being able to ensure a much greater stability and an air-block after their having been built up. The self-coloured wooden-houses are transported without materials of covering roofs and without any window panes, therefore, we suggest their walls to be treated with some wood protecting material and their roofs should be made of somewhat water-proof covering tiles or materials.