NF EN 13009 : 2000

Defines a method to determine the hygric expansion or contraction behaviour of building materials as a function of moisture content. Applies to mineral, porous hygroscopic materials. For other materials showing moisture-induced deformations, the described method can be suitably applied taking account of their specific moisture behaviour. It is relevant to material states when reversible contraction/expansion processes may be assumed, but not for states governed by irreversible processes such as shrinkage after material production or after initial drying.