Dörken Sistem, has been established as of April 2005 following the joint venture agreement between Dörken GmbH & Co. KG and Erdem Holding signed on February 4, 2005. Strengthened by 123 years of experience and know-how, Dörken Sistem offers customized solutions for waterproofing, drainage and protection of roofs, facades and foundations under "Delta" brand name. Dörken Sistem, produces foundation wall protection and drainage systems for Turkish, Middle East and Central Asian markets and also exports whole range of "Delta" products .