Skip to content
Measure, don't estimate

What is your façade losing — measured on your own wall?

Three temperatures are enough for a rough estimate: outside, on the inside face of the exterior wall, and in the room. From this follows what the façade costs on a cold day, what it costs per year, and what our three system tiers would change about that. Everything is calculated entirely in your browser — no data is transmitted or stored.

Your measurement

In the shade, not in the sun and not directly against the wall.

Room air in the middle of the room, roughly at chest height.

On the inside of the external wall, measured at the centre of the wall — not in a corner, not at the window reveal, not on a radiator or behind a piece of furniture. An infrared thermometer is sufficient.

Your building

Net area of the coated components, excluding windows and doors.

Pre-fills the unit price and utilisation rate with a reference value.

Unit price from the latest bill.

Annual utilisation rate; for a heat pump, the seasonal performance factor.

Depends on location; typically 3,000 to 4,200 Kelvin-days in Germany.

Final energy from the bill. For context only: the calculator will then tell you what share of it is attributable to the façade.

Result

Estimated U-value of your wall

Heat loss per day at 0 °C
Heating costs per day at 0 °C

Heating costs of the façade per year

Today

Easy Target value 0.8

ETICS Requirement 0.24

Plus Target value 0.2

Premium Target value 0.11

Savings per year compared to today

Easy
ETICS
Plus
Premium

Enter your three temperatures and the result recalculates instantly.

Calculate investment and payback Prices of the three tiers

Method: U = (Tindoor − Twall) / (Rsi · (Tindoor − Toutdoor)) with Rsi = 0,13 m²K/W, followed by the degree-day method Q = U · A · Gt · 24 / 1000. Thermal bridges, ventilation and solar gains are not included in this; a snapshot of a surface temperature is not a standards-compliant U-value verification. The target values 0,8 / 0,2 / 0,11 are our system values for the three tiers and not a certified U-value guarantee for your component; 0,24 W/(m²K) is the requirement value for external walls under Anlage 7 GEG. Calculations are performed entirely in your browser: no transmission, no storage.