Measurement of water retention properties of plaster. A parameter study of the influence on moisture balance of an external wall construction from variations of this parameter

In sever climate layers of plaster are put on the external surface of masonry to prevent or reduce penetration of driving rain into the wall construction. The material properties of the plaster are important for the moisture balance of the wall. This paper describes measurement of water retention properties of one type of plaster. It takes a long time to produce results from one material. Plaster are available in hundreds of qualities due to different compositions from the manufacturer, how it is mixed and applied on the building site, the weather conditions during the construction period and influence from the material it is applied on. Due to possible differences regarding properties from the laboratory test, numerical calculations have been carried out to check the influence from varying water retention properties on moisture balance for a wall construction. This paper gives the result from calculations using the WUFI program and calculation for periods of one year.