Traditionally, shutters functioned as a means of privacy and ventilation. This meant the pair of shutters closed together in the center, covering the entire window. Our shutters are meant to add an aesthetic value to your home and enhance its curb appeal. Therefore, shutters are determined not only by the window widths but by the other factors specific to the home such as window sizes, and the distance between windows. If you want a "standard width shutter", you are talking about a 12 inch or 14 inch shutter. Standard shutters are the more economical choice and in most cases one of these widths will work for your window. However, shutters should look proportional to your window size. So, if you have windows that are not common size windows, you might want to consider going with a custom built shutter. With shutter lengths, it really depends on the look you prefer. Some people prefer the top and bottom of the shutter to exceed the length of the brickmold around the window and some people prefer the shutter to line up with with window glass to get the more authentic functional shutter look.