Abstract: Tank vapor loss prevention has been paid great attention in the petroleum industry at home, which brings a rapid development of the built-up internal floating roof used in the existing tank for improvement so as to save energy and gradually replacing the integral internal floating roofs. For such a comparatively new technique in China, there has not been any manufacture and construction code as reference to the users. Therefore, how to control the quality remains a problem to those who apply them, for which reason listed in the paper are several points for attention in (the said roof) design, manufacture, installation and application so as to avoid unnecessary loss. View points and suggestions are given with related information and standards as reference.