Build it with what you have. Single should be fine for you. Look into heat-activated, non-electric, pneumatic openers. I think I saw that the Chinese Consulate, um, I mean Harbor Freight has them for about $20. There are also solar powered attic vent fans available at places like Home Depot for a bit more. If you go with single but find that you want more heat retention in the winter, look into preventing heat loss by air infiltration through small gaps in the walls and around the door and windows, insulate your north, east, and west walls, and consider temporary plastic over the windows to raise their R-value. I assume that in the heat of the summer you'll be leaving the place empty.

No storm windows--happily (or sadly for lovers of seasons!) we're in Northern California, where the climate is pretty temperate. (To wit: we've been able to just lean a board over the opening where the window once was for the past week...) At this point we've ruled out insulated glass and are down to deciding between laminated glass and just sticking with single-paned. (We learned that insulated glass will look quite different because the muntins need to be shallower to accommodate the thicker glass; this is apparently less of an issue with the laminated glass because it's thinner.) Still not sure we will get enough benefit from the laminated glass to be worth the extra cost, so it may just come down to the final estimates, which I hope to have today--but still welcome any other thoughts! This post was edited by artemis78 on Mon, Mar 17, 14 at 14:34

There is no comparison in terms of energy efficiency. Other than "Architectural Integrity" I can't imagine a good reason why anyone would install new single pane glass with a storm window instead of double pane insulated glass with argon gas filled panes and Low E coatings. In some regions people should be seriously looking at triple pane insulated glass, Low E glass with krypton gas. Consider the reality of heating and cooling costs in the future.

3bean3, Just now our 100 year old house is without its nasty white proud-sitting triple track aluminum storms for the first time since we moved in 11 years ago. It is lovely to see the original 6x6 and 6x9 windows unobstructed, until they are repainted and new storms are installed, design yet to be determined. But suddenly we are very aware of street noises, while before our house was very quiet. Also, we have one less layer of security in our northeastern urban neighborhood. I'll be very glad when we have settled on a design for storm windows and they are installed. In our neighborhood, a number of house-proud neighbors have chosen those wooden storms with fixed upper panels and interchangeable storm/screens below. I am torn about losing the ability to open window sashes at the top to exhaust hot air near the ceiling. Have you thought about installing nice full-length screens on the outside, and magnetic interior storms? Some on the Home Forum say that this will make your original windows deteriorate faster, since they will remain exposed to the elements. Others say that condensation is actually a greater threat to your windows and that interior storms do a better job of protecting them from condensation. I'd be interested in hearing what Oberon, WoW, Trapper, brickeyee, xoldtimecarpenter and sombreuil have to say to that. Apparently many historic preservation districts require this solution. But somewhere in my research I remember someone -- Mr Yapp? -- pointing out that our old houses never were meant to be without storm windows -- people just rotated full-length storm and screen panels twice a year. And my friends who live in a meticulously restored 1740s farmhouse in Connecticut do just that -- they are the most historically correct homeowners that I know. This question makes a small bungalow seem mighty appealing about now: possibly the best solution! Your thread has attracted the great wizards of the Home Forum: their guidance is invaluable -- I just wanted to add a couple of less technical points that I think you might want to consider. Lynn