Q: How do I take measurements for new storm windows?
A: You will need to measure the clear opening of the existing windows. This means when measuring width, measure from jamb to jamb (from the outside of the small wood strips that serve as the window’s “stops”). To measure the window’s height, measure from the sill to the top jamb (outside the top stop). You should also measure the spot where the top and bottom sashes meet, and purchase a storm window with sashes that correspond to the measurement. At the home store, you might find that the storm windows don’t come in the exact size you need. However, the plastic fins around storm windows are made to be trimmed. Use metal snips to cut equal amounts of material off each of the side fins so the storm window fits.