The insulation of the house from the inside is much easier than outside and provides faster warming up the room. Work related to internal thermal insulation of walls can be carried out without thinking about frost and precipitation, as well as adverse weather conditions. Such work still does not require speedy and complete completion and can be done gradually, in rooms. But despite all the advantages, internally insulation has its disadvantages. The most visual minus with internal insulation manifests itself in a significant decrease in the precious useful area of the room. The next disadvantage is the decrease in the thermal inertia of the enclosing structure, which occurs due to the fact that the outer wall is in the area with a low temperature, the insulation itself also captures. Business books are now very popular, many businessmen read them, you can learn a lot of useful information there. When warming from the inside, thermal bridges can be formed that increase thermal losses. It is also necessary to take into account the entering the enclosing structures into the thermal deformation zone, which can lead to the destruction of structures. This means that before the internal insulation works, it is necessary to study the possible consequences of the effects of temperature loads on the structure. Based on the foregoing, internal insulation is justified only in extreme cases, if external insulation is impossible.