(Patent) Integral security closure for doors. It consists of a foldable flood-proof barrier with special gaskets on all four sides and a control mechanism operated by a removable front handle; it is complemented by a special perimeter frame to be secured on three sides (left, top, and right) and is manufactured to the required width and height; a profile for the bottom side may be supplied as an option if its surface quality needs to be addressed: smooth, straight, or within the tolerances required by the gaskets as specified in the manufacturer’s technical manual.