Sachverständiger Ingenieurgutachter für Dachkonstruktionen

Dachspezialisierter Sachverständiger für Planung, Beratung, bauphysikalischen Wärme- und Feuchteschutz, Schadens- und Ursachenfeststellung / Baubegleitende Qualitätssicherung / Sanierung von Tauwasserschäden und Schimmelbefall / Bewertung Produktmängel, Praxistauglichkeit und Langzeitbewährung von Dachbaustoffen

jens drefahl	Diplom-Ingenieur Archiktekt Ingenieurgutachter Dachsachverständiger
Öffentlich bestellt und vereidigt für Dachdeckungen, Abdichtungen und Dachbegrünung Bestellung von der IHK Berlin - zuständig seit 1995

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Dachabdichtungen - Praxiswissen Langzeiterfahrung | Abdichtung Referenzobjekte | Dachgarten Tiefgaragen | Extensive Begrünung | Gründachmängel | Metall- Glas & Ziegeldächer | PU-Beschichtung Flüssigabdichtung | Dachinstallationen Solar HT | Wärmeschutz Tauwasser & physik. Dachsanierung | Publikationen | Schulung | Impressum International activities
	International activities Professional Portrait of Jens Drefahl
	Engineer-architect since 1969. In 1973 founded an own office. Projects: Apartment-, municipalbuildings, Solarhouses and sport-centers. Since 1973 he realized with his own building firm energy reduction houses with an active and passive warmth extraction. The first passive solar house planed by him named: Flower Hill House.It was reported far beyond Europe in all medias, inclusive of television. Jens Drefahl developed parallel different methods for ecologically and economic roofing-technologies. The todays level of technic for planted roof-systems up to roof control-technologies in Germany is essentially based by this innovations. Jens Drefahl got financial support for his innovations from the granting of patents in Europe and the USA through German Ministery for Research and Technology (BMFT). The aim of the research and the development was creating
	economical and ecological roof-systems for flat and steep roofs esthetic humane roof-elements to bring nature in the town and industry-roofings biotop- roof-covering-systems care free for generations
	Scientific research shows that planted roofs - executed 20 years ago - should last for more than 100 years. The additional positive effects of these innovations are:
	collection of rainwater to relief the burden on the sewage system energy saving for air conditioning in industrial buildings.
	Because of the intensive support by the medias for this young roofing technologies the german building scene since 1988 experienced an astonishing boom. Today the new built green-roofes areas cover about. 4-5 million m ² /year. The disadvantage of the boom: Every roofer claimed to be a gardener and the gardeners turned to roof specialists. They experimented without experience in a market without normative regulations. Numerous failures and company collapses threatened to endanger the image of the planted roofes. Jens Drefahl retired from his company shareholdings in 1992. He influenced with numerous publications, including a reference book: Level of the Technique for roof insulation, control-systems and roof planting. Basic norms for roofing standards are also important for the legal building codes. In 1995 Jens Drefahl became the official legal expert for roof sealing and roof planting by the IHK (Industrie-und Handelskammer) Berlin. The main emphasis of the activities of Jens Drefahl:
	advice builders in ways to optimise the building process quality control at mayor construction sites - trouble-shooting in europe. officialy recognized sworn public expert on roof sealing and roof planting mediator between quarrelling parties in- and outside the courts optimise cost, production and technical advice
	First Solar-Modul-House (passiv) in Germany (JDrefahl - Architekt