Lets say your windows are being measured and the pro wants to know if you’re happy with the dimensions of your existing window treatments. How will you answer?
Once, I installed a set of wood blinds which another pro had measured. He had sized them perfectly to cover the window trim but the old blinds were a few inches over on 3 sides.
If the prior dimensions were not a mistake then the blinds were either left over from another job (and pressed into service) or, possibly, had been over-sized as an aesthetic consideration. I was relieved that the new blinds were exactly what the customer had in mind.
Years ago, vertical blinds were often measured floor to ceiling as a design choice which, over time, has become less popular. Today, verticals are typically ordered with minimal overhang.
Sometimes a homeowner orders window treatments to cover unsightly trim (which would be costly to replace) even though there is ample depth for an inside mount.
Consider your options and have the conversation before the order is placed.