Check if you would like shutter to be fitted inside the recess of the window (Reveal Fit) or on the outside (Face Fit). With reveal fit it is optimal to have about 60mm of room between the outside of the sill and the window (or window catch).
Unless you have casing, trim, cabinets or other obstructions that will interfere with the shutters we HIGHLY recommend Face Fit (outside mount) shutters as they are easier to measure and install.
There are 2 factors that determine whether a Reveal Fit (inside mount) is possible: Frame depth and squareness.
Window Frame Depth
In order to mount inside the window frame you will need a minimum 60mm of depth. Measure from the front edge of the window frame to the window or the first obstruction, such as a window catch or crank.
Window Frame Squareness
In order to determine if your window is square, measure the window diagonally. If the 2 measurements differ by more than 10mm we recommend an outside mount shutter.