Abstract: The present invention relates to a device and a method for DED or WAAM, comprising a welding torch configured to generate an arc for generating a melt pool on a surface of a workpiece, and a wire feeder configured to feed a wire towards the melt pool to generate a weld seam on said surface, and an enclosure enclosing at least part of the workpiece and comprising a process atmosphere with a process gas, wherein a sucking device sucks part of the process gas out of the enclosure and thereafter re-introduces the process gas into the process atmosphere, and wherein the enclosure comprises or consists of a flexible housing or a tent and in the sucking device is connected to a buffer volume or a pressure stabilizing unit.