How many shutter panels do I need for each window? Typically, the the large the surface area of your window, the more shutter panels you’ll need. The optimal design is to use one panel for windows up to 26 inches wide, two panels for windows up to 50 inches wide, and four for windows up to 98 inches wide.Single wide panels are not as room-friendly as two separate panels. Sometimes, wider panels won’t fit flush against the wall due to their size. Multiple smaller panels don’t have that problem.For those windows that you’ll want to open or shut regularly, you’re usually better suited with multiple panels, since they’re easier to open and have additional support from the shutter frame when you do operate them.