Water vapour transmission rate (WVTR)/ Sd- value (water vapour diffusion-equivalent air layer thickness)
Determination of the Sd value according to the gravimetric method on diffusion open and diffusion inhibiting materials with Sd values of approx. 0.03- 10 m ( equivalent to a WVTR of approx. 4- 800 g/(m²xd) depending on the material and test conditions) as a quintuple determination. For diffusion-inhibiting, diffusion-blocking and diffusion-proof materials with Sd values of approx. 10- >1500 m (corresponds to a WVTR of approx. 0.005- 125 g/(m²xd) depending on the material and test conditions), we recommend the more rapid and more cost-effective electrolysis method (then deviating from the standard as a double determination).
optimum: 5 DIN A 4 sheets without folds, creases or other damages
WVTR / Sd value water vapour barrier materials Determination of the SD value (water vapor diffusion equivalent air layer thickness) of building materials and products that are used as vapor barrier, electrolytic measurement according to ISO 15106-3 (suitable for Sd-values in the range of approx. 50 - >1500 m).
WVTR/ Sd- value breathable materials Determination of the Sd- value (water vapor diffusion equivalent air layer thickness) of building materials and products, which used as permeable (breathing) materials, gravimetric measurement according to DIN EN ISO 12572 / DIN EN 12086 (suitable for Sd-values in the range of approx. 1 - 100 m).