Root-resistant waterproofing Kurt Michels (D) Lecturer at the Roofing Vocational School in Mayen, member of the FLL task force „green roofs The root-resistant waterproofing is a pre-requisite of durable and secure green roofs. For this purpose the FLL has developed a special testing method which is based on long term trials with root-aggressive plants in standardised test containers. Currently more than 70 waterproofings, made of different materials (bitumen, plastic, elastomer, etc.) have passed the test successfully.
	Innovative and reliable green roof build-ups Roland Appl (D) Technical Director ZinCo GmbH, Unterensingen, member of the FLL task force „green roofs How has a green roof system to be designed to guarantee the protection of the waterproofing, the drainage of excess water and the supply of the plants with substrate, water and nutrients in a sufficient way. Roland Appl will discuss and present the special advantages and problems of a broad range of techniques including one-layer, multi-layer and thermal insulating green roof build-ups.
	Logistic solutions on site and practical experiences Hans-Jörg Kiesewetter (D) Green roof contractor, ProNatur, Metzingen Questions of logistics are playing a decisive role for the planning and installation of green roofs. This implies the calculation of the material requirements, the delivery form, the transfer of the materials to the building site/roof and the scheduling of the complete building project. Hans-Jörg Kiesewetter will reveal possible weak spots within the logistic chain by presenting concrete examples.
	Potential sources of error and how to avoid them Bernd W. Krupka (D) Landscape architect and green roof surveyor, former leader of the FLL working group "green roofs", recognised writer of specialised books, Bad Pyrmont The knowledge of the potential sources of failure and the consequent observance of guidelines and instructions helps to avoid lacks and damages on green roofs. In addition the installation of high quality material by an experienced staff is another precondition for reliable and durable green roofs. Bernd W. Krupka will present the most frequently problems (e.g. gappy vegetation layer, damage caused by wind or water erosion, pest infestation, water loggings, lacks in the substrate layer and the green roof build-up) and practical strategies for planers and green roof contractors to avoid these problems.