On many older homes storm windows are fitted over the older single pane windows to provide better insulation and cut down on energy costs. This is usually a cheeper route then installing new double pane windows and on some historic homes it isn’t allowed to replace the older windows with new ones leaving the homeowner no choice but to have storm windows installed. The drawback is they are not easy to clean. Some are surprised to hear how much it will cost to have them cleaned professionally, but this is because the storm windows have to be taken out and cleaned separately in addition to cleaning the original windows. Since it’s like cleaning two windows in one the price will normally be double. So what is the difference on a double paned window? Any new window will most likely be double pane. This is two pieces of glass built into the window side by side. Since the window is sealed so no air or moisture can get in between the glass there is now way (and no reason) to clean the inside and it is only necessary to clean the two exterior sides just as you would on a single pane glass window. Therefore the cost to clean newer double paned windows is considerably cheeper.
Window Cleaning Tips