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This article evaluates the accuracy of 3D models made from point clouds obtained from photogrammetry. Photographs were taken from ground level and using a drone, and data processing was performed in 3DF Zephyr. The models were compared with the actual dimensions of the buildings. Four different building objects with varying degrees of complexity were analysed. The aim of the research is to analyse the conditions for taking photographs and how they are transformed into a point cloud, and to see how and whether the complexity of the shape of the facade affects the accuracy of the 3D model made from the point cloud. The inaccuracy of the point cloud in the form of point spread for all analysed cases was 1.8±0.4 cm on average. The largest measurement error was found in the case of a multi-storey building. Despite the presented inaccuracies, it was considered advantageous to use the point cloud obtained through photogrammetry in the inventory. No difference was observed in the accuracy of the model depending on the complexity of the building. Recommendations were made regarding the conditions for taking photographs.

The moisture content in historical masonry walls, particularly on the ground floor, caused by i.e. lack of damp insulation, is a phenomenon of common occurrence. It is usually analysed in terms of mycological changes, thermal insulation and frost damage. The paper discusses the influence of the increased moisture content on the weight and load bearing capacity of the structure. The determination of moisture content in masonry elements, performed during the inspection of the building, provides information from which an increase in the structure's weight can be defined. Reliable tests for the moisture content and compressive strength of masonry and mortar components are invasive, and the number of testing in historical buildings should be limited to the minimum necessary to preserve their vintage nature. As a result, the received overall picture of the work of masonry may not be consistent with its actual state since historical buildings could have been rebuilt or repaired, and consequently, contain masonry conversions made of various materials with different properties. Absorbability can serve here as an example as it is a factor that disrupts a reliable determination of load bearing capacity values of masonry structures. The article attempts to determine the change in load bearing capacity of a moist masonry structure compared to the original -in the air-dry state -for various types of historical masonry and mortar components. The main influence analysed was due to capillary action, whereas the effect of other sources of moisture, i.e. salinity, was excluded.

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