The material under study in this paper is a gypsum composite board, which is a sustainable material, and therefore attracts scientists’ attention in the recent years. This material is of a great importance for Latvian economy, since Latvia has gypsum mining sites and has developed a tradition of gypsum manufacturing. The goal of the study was to compare the mechanical properties of gypsum boards from different manufacturers. For comparison of strength one cement board was tested as well. To complete the study a specific experimental setup was developed and is demonstrated in this paper. The results obtained are experimental values, useful for a scientific community because these can be used for CAD modelling in the future. In this paper the experimental results were used to create FEM models in ANSYS program and complete simulation. It was discovered that some gypsum boards have different physical properties in longitudinal and transverse directions, while for other properties do not differ depending on the direction. In this study, the cheapest board had the yield stress of 2.76 MPa in the longitudinal direction, 1.87 MPa in the transverse direction, while the more expensive board was homogeneous, and the physical properties did not change depending on the direction and the average yield stress was 2.19 MPa. The values obtained in the tensile test in other studies of gypsum boards for other manufacturers are even lower - 1.10 MPa in the longitudinal direction and 0.64 MPa in the transverse direction.