These three storm sash, are traditionally made by Westbrook in our wood shop. They are the first set that are getting installed on this project. They are all vertical grain fir, with traditional storm sash opening hardware, that are easily opened from the inside. You can see them in the raw on the shop assembly table, before They are pre primed before fitting in the field. Once fitting is done, its back to the shop for priming the cuts and installing the glass. These storm sash have a cross piece that matches the prime sash meeting bar. They are simple compared to the arch top storms I did awhile back. The link is here if your interested https://builttowithstand.com/projects/historic-window-arch-top-new-storm-sash/
Storm sash definitely protect the prime sash from weather, and provide major resistance to heat loss and sell as noise reduction. The bonus is that they can be maintained for longevity…… Something you can’t get with modern insulated glass windows, that need replacement every few years. Feel free to contact me if you have any questions!