Widespread use of the sandwich walls in frame buildings in Russia is the result of high requirements to energy efficiency of the coating constructions. The defects of facing masonry were caused by insufficient level of experience at the processes of design and construction of such kind of buildings. The purpose of the article is to describe the main causes of the defects of facing layer of sandwich walls. Conclusions about the rationality of the cellular bricks with the results of experimental work are also shown in the paper.