In the case of insulation and renovation in partial sections, it makes sense to adhere to the following sequence of renovation measures, both with regard to an efficient construction process and with regard to the efficient use of financial resources:
1. Step: insulation top floor ceiling
With relatively little financial outlay can be achieved by the insulation of the top floor ceiling a significant reduction of heating demand. Around 20 to 25 centimeters of insulation are now considered state of the art.
2. Step: Swap windows and doors
The best thermal insulation on the façade is not very successful, as much of the heat is lost through leaky windows and doors. Therefore, these mounting elements should be checked for leaks. Before any replacement, you should exhaust all other options, such as using new sealing tapes, adjusting the hardware or replacing the glazing when the window frames are still functional.
3. Step: insulation of the cellar ceiling
If there is a cellar, which is not developed as a living room, then the insulation of the basement ceiling ensures warm feet. If there is underfloor heating in the upper storeys, then after the insulation, the flow temperature of the heating system can be throttled and alone a considerable saving effect can be achieved - while at the same time increasing living comfort. An insulation thickness of at least ten centimeters is recommended, as far as the respective room height in the basement floor permits.
4 step: insulate outer walls
For cost reasons, the insulation of the outer walls should happen in the course of the facade renovation. On average, the outer skin of a building must be renewed or rehabilitated every 20 year anyway. A new coat of paint is the minimum solution if the underlying plaster still has sufficient strength. Ideally, the insulation can also be glued directly to solid plaster layers and additionally secured with façade anchors.
If more than 20 percent of the plaster surface of a house is renewed in the course of facade renovation, the Energy Saving Ordinance already prescribes the application of additional thermal insulation. Insulation thicknesses from twelve to 15 centimeters are actually considered a minimum standard today.
5. Step: Optimization of the heating system
The renovation of the heating system is at the end of the thermal renovation of the building. Due to the savings achieved, the respective heating system can be dimensioned much smaller.
However, it is not always necessary to replace the boiler and change the entire energy supply. Even smaller additional measures are quite successful, such as the subsequent insulation of distribution pipes, a modern control system or the alternative use of thermostatic valves.