In this study, the samples of Scotch pine, chestnut and oak wood, which are widely used in the production of wood products, were heat treated with the ThermoWood method for 5 hours at 150°C, 4 hours at 170°C, 3 hours at 190°C, and 2 hours at 210°C. Variable effects of decreasing the processing time while increasing the temperature in heat treatment on wood properties were investigated. For this purpose, a total of 1440 samples were prepared from three wood species. After heat treatment, climatic treatment was applied to the samples at 20°C temperature 65% relative humidity, 40°C temperature 35% relative humidity, 10°C temperature 50% relative humidity conditions. In these examples, according to the relevant standards; density, bending strength, modulus of elasticity, thermal conductivity coefficient and heat permeability value changes were determined. As a result, it has been determined that while the losses in the physical and mechanical properties of wood due to structural deterioration are low in low temperature and long-term heat treatment concepts, these losses increase more in high temperature and short-term heat treatment concepts. In the samples with 170℃/4s and 190℃/3s heat treatment, the self-load and thermal conductivity coefficient of the wood decreased, the insulation and mechanical resistance values increased, and it was determined that the suitable climatic condition for wood use (in terms of equilibrium humidity) was 40C/35%.