What is ISO 12571 about?
ISO 12571 specifies two alternative methods for determining hygroscopic sorption properties of porous building materials and products:
- Using desiccators and weighing cups (desiccator method);
- Using a climatic chamber (climatic chamber method).
The desiccator method is the reference method.
The methods specified in ISO 12571 can be used to determine the moisture content of a sample in equilibrium with air at a specific temperature and humidity.
NOTE: This document does not specify the method for sampling.
Who is ISO 12571 for?
ISO 12571 on building materials and products is useful for:
- Builders
- Civil engineers
Why should you use ISO 12571?
Hygrothermal refers to the movement of heat and moisture throughbuildings. Sorption behaviour describes the ability of a hygroscopic product to absorb or release water vapour from or into the air until a state of equilibrium is reached.
ISO 12571 provides two test methods namely the Desiccator method and the Climatic chamber method to get hygroscopic sorption properties of porous building materials to check the moisture content of test specimen in accordance with temperature and humidity.
These test methods assist you in determining the amount of water vapour absorbed or released from or into the air until a condition of equilibrium is attained in order to enhance the performance of building materials.
ISO 12571:2021 contributes to UN Sustainable Development Goal 9 on promoting industry, innovation and infrastructure; Goal 11 on making sustainable cities and communities; and Goal 13 on making climatic actions.

