Permanently increasing energy costs require a moderate and economical handling of the valuable raw materials. The use of high - speed architectural doors basically previously led to saving energy, the heat design insulation of the doors used however often was neglected. Therefore as the first and only producer in the world, EFAFLEX will as of immediately offer double walled insulation laths in thermally separated and insulated models for exterior high - speed doors – now in serial production. Especially in the times between uses of a high - speed door, this measure ensures that it will again extensively reduce the unwelcome loss of heat. According to DIN EN 13241-1, for the first time a steadily built-in door has extreme high heat insulation. According to the manufacturer, U values of around 0.8 W (m²K) are reached for the entire surface of a steadily built-in high - speed door.