The reliability of historical buildings` brick structures is usually evaluated on the basis of analysis based on empirical formulas that use characteristics of brick and masonry mortar, which are obtained as a result of testing samples of materials taken from the structures. The practice of making such evaluations often shows an obvious discrepancy between the visual state of the structure and the analysis results obtained. Brick-masonry that does not have signs of the load-bearing capacity loss may be evaluated as emergency brick-masonry, and structures that have clearly lost their integrity are sometimes assumed to be sufficiently reliable. The currently valid regulatory documents provide for the possibility of using standard samples for direct evaluation of the strength of brickwork, but it requires adaptation to the conditions of the of historical objects` survey. This paper presents substantiation for the need of using standard samples to evaluate the strength parameters of historical objects` masonry.

The transition to strength classes in the design of wooden structures allows correctly assessing the level of reliability of the designed constructions. The article presents a comparison analysis of the safety factor values in the Russian regulative standards and those previously in force and assesses their impact on the reliability level. The influence of the transition to probabilistic normalization of the strength properties of elements and structures made of wood in general using strength classes is substantiated. The development of the approach will significantly improve the reliability and safety of wooden structures, especially large-span structures and multi-storey buildings.