Abstract: A storm window assembly for attachment to an existing window, either on the inside or the outside, for improving overall insulation ability of the window. Included is an extruded female frame retainer which is permanently attached to the existing window casing. An extruded storm window frame has a male member which snaps into this female retainer which pivots as needed to provide a good air seal. The storm window glazing is inserted into a slot in the frame. In this slot are soft gripping fingers preferably three pairs, which hold the glazing in the frame by friction alone, obviating any glue or other adhesive. These fingers are sufficiently soft and slanted inward that they guide inwardly during insertion of the glazing into the slot, but are also sufficiently firm and slanted that enough opposite gripping pressure is exerted to prevent the glazing from sliding sideways or out of the frame.