A house built in 1890 shows what this looks like: annual heat demand fell from about 40,000 kWh to below 15,000 kWh, a reduction of more than 60 %. In a block of flats from 1960, the U-value of the exterior wall fell from 2.63 to 0.096 W/(m²K); the inner wall surface rose from 13.0 to 19.7 °C. The measurement data and the case study can be found on the measurements page.
How to proceed:
- Enter your address in the address calculator. It shows your building in 3D, estimates the facade and attic-floor area and calculates savings and payback for each package.
- Choose a package. Easy, Plus, Premium and Komplett differ in their guaranteed U-value (0.8 / 0.2 / 0.11 / 0.10 W/(m²K)). Every package comes with a written U-value guarantee.
- Check funding. The funding check in the calculator shows grant and own contribution.
Why a thin build-up suits old buildings: the layer is only about 1 mm thick. Window reveals, roof overhangs and plinths stay as they are, and the facade keeps its character.
Comfort, not just kilowatt-hours
Warmer wall surfaces feel warmer. In the 1960 block of flats the inner wall surface rose from 13.0 to 19.7 °C. This does not only save heating energy (1890 house: over 60 %); it also makes rooms more comfortable at the same air temperature and keeps mould away. More on this in the guide “Raise wall surface temperature”.
Evidence
CE marking to EN 15824 (declaration of performance PSC250T-2026-01) · TÜV NORD Verified Product, mark ID 141649 · U-value guarantee per package · Measurements · All evidence and case studies