In the research shelter materials can be stored in outdoor climate conditions without being exposed to wind-driven rain. However, the shelter is open enough, that the moisture of outdoor air can freely effect on the materials. The shelter was used in developing the Finnish mould growth model, the material samples and layered structures were stored there, and their moulding was monitored. These moulding events in real and measured outdoor climate conditions were then compared with the mould model, and this information was used to calibrate the model. The shelter can also be used to do other monitoring tests on materials in outdoor air conditions.