Results of tests of compressed masonry elements from small cellular blocks with foam concrete cores with short-term action of axial load are presented. The nature of the destruction of experimental elements with various reinforcement schemes and the degree of joint work of monolithic foam concrete with gas silicate masonry in a complex structure is established. The strength of these complex structural elements was evaluated and the effectiveness of their application was shown to increase the load-bearing capacity of masonry of walls and pillars in the construction of buildings of small and medium storeys. The strength gain of the compressed elements, due to the reinforcement of the cores with spatial frames, ranged from 10,5 to 12,5 %, the deviation of the theoretical strength values of the centrally compressed complex sections from the experimental ones did not exceed 10 %. One and a half-two-fold reserve of strength of solid and reinforced by foam concrete cores of masonry in case of its application in bearing walls of five-storey building was revealed.