U-value estimation

Optimal Timing: Take measurements 30&ndash;60 minutes before sunrise . This is the most stable thermal state, avoiding solar heat interference.
Stability: Ensure the outdoor temperature has been relatively stable for the last 6&ndash;12 hours.
Placement: Place surface sensors on a flat part of the wall, away from corners, windows, or structural columns (at least 1.5 times the wall thickness away from any edge).
Instruments: Use high-precision contact thermometers for surfaces and calibrated air temperature sensors. Enter data with a precision of 0.1 &deg;C.

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Thermal Performance Standards

This tool is based on international standards ISO 6946 (calculation methods) and ISO 9869-1 (in-situ measurements of thermal resistance). In Cyprus, the current national regulations for building energy performance typically require wall U-values to be ≤ 0.4 W/(m²·K) for new constructions or major renovations.

Disclaimer: The results provided by this calculator are for informational purposes only and represent an estimate based on your manual inputs. They do not constitute an official energy audit or certificate.

For a detailed building fabric analysis or to obtain an official Energy Performance Certificate (EPC), you must consult a certified Energy Auditor or Structural Engineer.

I have read the information and agree that the results are estimates. I understand that for official conclusions, a certified expert is required.

Thermal Performance Standards

How to Conduct Measurements