GENERAL: how do Eurothane boards behave in humid environments?
The damp absorption of Eurothane is almost non-existent. The Eurothane products are also tested for damp absorption as part of the ATG inspection. After complete immersion under water for 24 hours the water absorption is limited to a couple of %.
In practice this situation does not occur; on the other hand the majority of Eurothane products are faced on both sides with a facing that absorbs little to no damp (e.g. aluminium film).
This means that Eurothane products can often be used even in less favourable weather conditions and do not contribute to sealing in extra damp in a construction.