This refers to the way your window treatments will attach to your window. Inside mount measurements are made inside your window. You do not have to make any adjustments for this type of measurements as we will make the adjustments necessary for it to fit perfectly recessed in your window.
For an outside mount measurement please measure where the window treatment would exactly cover.
Outside mounts can be used to install your window treatments on walls, doors, and trim. Please give us a call or send us an email if you are not clear on how to approach this.