How to Buy - Measuring
Storm window sizes are determined by measuring your existing window opening as shown. Record opening width A first and opening height B second. Round down to the nearest 1/8”.
Many kinds of windows can be installed Blindstop (inside mount) or Overlap (outside mount), or you can have the windows made to the exact tip-to-tip measurement desired.
Blind Stop Installation (inside mount)
Measure your existing window opening listing width first and height second. Often, the vendor of the window will automatically downsize your window to ensure the proper clearance and fit.
Flush Mount Models
The Flush Mount Window features an expander that goes all the way around the window. It brings the outside surface of the storm window flush with the prime window casing for a smooth appearance. Ask for flush mount options when ordering.
Overlap Installation (outside mount)
Overlap windows mount over the window opening. Measure your existing opening. Often, manufacturers will automatically upsize the window allowing for a proper fit.