For wall insulation, you can use such material as — polystyrene foam. It is great for internal insulation of a private house. To warm the house from the outside, you can use foam. In order to insulate the walls, a special metal crate is installed made of metal profiles. You can also use wooden bars for the crate. The crate is installed in order to put the heat -insulating material there, and in the future, either drywall or any other material is installed on it.