Both diffusion and convection were taken into account when studying the transfer of water vapour in this project. In the first stage of the project, equipment was developed to determine how water vapour moves inside wall structures. With the laboratory equipment the temperature, moisture content and pressure differences in both the indoor and outdoor air were adjusted. In the second part of the project, calibration and structural tests were made with the equipment, which enabled researchers to acquire completely new information on the hygrothermal performance of wall structures in different conditions. In the future, other structural solutions and their hygrothermal performance can be easily tested.
More information about the new equipment and its functionality as well as the results of the structural tests can be found in Publication 96 (in Finnish).
The project was financed by National Technology Agency of Finland TEKES.