Double hung shutters offer the maximum in shutter adjustability, but without the proper design - double hung shutters will sag and perform improperly. Also, double hung bi fold shutters must be designed so that the panel height is greater than the panel width due to the leverage factor. Shutters ordered with a width dimension more than the height will sag.
Also, notice in the diagram below how the double hung shutter has a slight gap between the panels and also creates a solid wood section where the shutter panels meet. This is because your rails are effectively doubled to accommodate the structure required of top and bottom panels. This is important to note as you can not tilt this portion of your shutter panel open for view or light. However, with all of that said, double hung shutter can be the perfect solution for the right design application.
We would love to help you with your double hung shutter project. Also, please check out our online shutter cost estimator for a quick idea of what your project might cost. One additional comment, double hung shutters are 40% more expensive than the approximate price indicated on our cost calculator for a standard panel shutter.