We needed to buy blinds for one of our bedrooms. I took my measurements and off to The Home Depot we go.
We purchase a nice set of faux wood blinds, get them trimmed to size and take them home to install. Everything goes smoothly, until we notice...
The damn things were cut too short. They were too narrow and let in too much light from each side.
Did the Home Depot employee screw up the cut? Nope. He took 1/8" off of each side (for a total of 1/4") to ensure clearance in the widow casing. The cuts were perfect.
I remeasured the window and found that my casing isn't square back to front. The window is recessed about 3 inches, allowing us to install the blinds inside the casing. Right against the window, the inside measurement was 36 3/4". At the front of the casing, where the blinds were actually installed, the measurement was 37 3/16". A total difference of almost a half an inch. Combine that with the additional 1/4" cut off the blinds, our gap measured over a 1/3" on each side of the blinds when installed.
Lesson learned. When measuring for blinds in a recessed window, never assume that your window casing is square. Make sure the casing is measured at the actual point where the blinds will go.
Otherwise you might piss away a set of blinds like I just did. Fortunately the faux wood blinds were only $60 and not $400 like the real ones are.
And the new blinds cut with the proper 37 3/16" measurement? They fit perfectly and look great.