Durability of roofs has been increased by using polymer modified bituminous materials. But increased number of roofs permeability from polymer-modified roofing membranes argue about serious problems in lap joints durability of roofing membranes. By analysing this problem were overlooked the bituminous roofing membranes history and their characteristics. This research analysed the mechanism of seams formation and impact of welding technology on properties of durability and maintenance such as strength, thickness, appearance of not welded places and seams permeability. There was made overlook of worlds literature and experience. Also there were found the basic roofing membranes lap joints welding problems. The main additional parameters for seams evaluation were defined: the final thickness of seams, seams permeability, appearance of not welded places. The solutions were suggested for the further investigations of these parameters.

Article in Lithuanian