Abstract: An auxiliary or storm window is installed inside of a conventional prime window of diverse dimensions. Plastic extrusions are cut to size on the job and are fastened around the periphery of the inside of the window. The extrusions have slots which receive plastic panels. The panels form a closure for the inside of the window. Vertical and horizontal support members are installed between the sill and header and between the side flanges on large windows to accommodate a plurality of panels which make up the closure.

Abstract: An auxiliary or storm window is attached to the inside of window frames. Transparent acrylic panels having lengths which exceed the transverse dimension of the frames and widths which are less than the longitudinal dimension of the frame are cut to fit the inside frame of the window. Elongated frame members having longitudinal slots which engage the edges of the panels are positioned on the sides and on the top of the panels. Track members join adjacent panels along their length to form a sheet of panels of the correct size. Each track member has a flat longitudinal surface which is fastened across the frame between adjacent panels. It has an upwardly facing slot to engage the panel above the track and a downwardly facing slot in which a gasket is placed to seal the track member to the top frame of the panel below it.