Static extractor for building roof has plate with central opening having folded lip and two part cap

摘要

The static extractor for a building roof has a plate (3) with a central opening (4) having a folded lip (5). A two part cap (6) has an upper part forming the cap proper and a lower part forming a tunnel. The components are made of ceramic and are connected by spacers (7) defining a gap between the upper edge of the lip and the bottom of the cap. The gap is approximately eight times the diameter of the passage at the level of the lip.