Sometimes it is impossible to preserve your building from low temperatures from the outside, so carrying it out on the inside is the only way to go. Such operation undertaken internally, however, is more tricky than normal external solution.
There exist various factors that can make it difficult.
Specialists think that insulating walls from the inside is less profitable than doing it externally. Still, there are occasions when it can solely be done internally. Insulation from the inside is seldom applied since it involves various issues. It is more complex and risky than the warming of the building externally, known for many years, so conclusions were drawn from the errors made and a few ideas were recommended that exclude most of them. The biggest issue in a structure insulated internally is that after such a procedure its constitution (external walls, ceilings) is located in the unprotected zone. While there is no insulation, the whole surface has a significantly higher temperature (to our detriment, due to the high heating expenses) and only a little outside fragment is below 0 ° C. After installing the insulation from the inside, the temperature below 0 ° C will apply to the bigger diameter of the surface, because the heat will cease running through it. This makes the wall much colder and more exposed to low temperatures.
In case of insulation from the inside, the walls must first be protected against humidity. The penetration of water vapor coming from inside the building into the middle of the barrier is counteracted by vapor barrier with a properly selected diffusion resistance coefficient.