This would only apply to clients in my area of operations. The short answer is, "no," and here's the reason: most of your home windows are gas-insulated and double-paned. Leaded glass windows in and of themselves are not insulated. There are ways to overlay insulating materials on leaded glass, but that is beyond the scope of my small garage "studio." What I recommend is that you place my custom-made windows INSIDE the existing windows; this does a couple things; 1) it maintains your insulation and 2) it protects the leaded glass piece from exposure to the elements. Below are transom windows I created for our dining room. They are inside the original windows, but you have to look closely to see that there are still clear glass exterior windows.