The importance of moisture buffering for indoor climate and energy conditions of buildings

A new Nordic test method specifies a test protocol for determination of the so-called Moisture Buffer Value (MBV) of building materials. But how important is moisture buffering to determine the indoor humidity condition of buildings? The paper will present the new MBV-definition. Although it is primarily a value meant to characterise the moisture buffer property of building materials, can it also be used as a calculation parameter in design of buildings? And how does moisture buffering compare with the effect of ventilation of buildings? Is it possible for instance to use the benefits of moisture buffering to save energy by reducing the requirement for ventilation in periods, and still maintain the same quality of the indoor climate? The paper will outline some possibilities for analytical/numerical calculations, and will answer some of the posed questions on the probable benefit of taking moisture buffering into account as a design parameter.