URSA Spannfilz SF 38

Austrian rated heat conductivity value. This value is to be used for thermal performance calculations (energy performance certificates, etc.).

Definition for insulating materials: A value that is not exceeded by at least 90% of production (probability of acceptance 90%), valid for an average temperature of 10°C and the state of equilibrium for humidity at 23°C/80% relative atmospheric humidity.
Source: ÖNORM B 6015-2

Proof:
- Nominal value from the CE Declaration of Performance with corresponding humidity conversion factors
- Nominal value from the European Technical Approval with corresponding humidity conversion factors
- test certificate for the rated value in accordance with ÖNORM 6015-5

The water vapour diffusion resistance (μ value) is a parameter to determine the exchange of moisture of a construction material. The lower the μ value, the easier it is for vapour to penetrate a substance.

Definition: Ratio of the vapour diffusion coefficients of the air and that of the relevant substance.

Proof: Manufacturer information