Thermal insulation: insulate the facade and basement ceiling
For facade insulation or insulation of the basement ceiling there are different insulation materials. For example, glass wool, perlite, polystyrene such as Styrofoam or rock wool such as Rockwool. Facades are insulated from the outside, in the core or from the inside. If the masonry is double-skin, core insulation is the easiest and usually the cheapest. Exterior insulation makes sense if you wanted to renovate the facade anyway, interior insulation is suitable for half-timbered houses or houses that are listed buildings.