I finally measured my garage and found out it's 2 feet narrower than I thought for 6 years
Pulled out the tape last Saturday because I was eyeing a $400 workbench on sale at the hardware store in Council Bluffs, and turns out the wall is exactly 19 feet 4 inches, not the 21 I'd been telling myself, so the bench wouldn't fit the way I planned, and now I'm wondering if anyone else has measured a space wrong for years without knowing it.
That 21 foot number you had in your head is exactly how it goes, you just keep repeating it back to yourself until it feels true. I did the same thing with my shed, swore it was 12x16 for years because thats what the guy who sold me the house said, then I went to lay down a 4x8 sheet of plywood flat and had like 3 inches to spare on the short side. Measure the actual wall to wall at the floor and again at bench height, because drywall and baseboard can eat an inch or more, and dont forget the garage door track hangs down a foot in most of these older places. If the bench is 6 feet and you only need a couple inches, you can notch the back legs or run it along a different wall, just check where your outlets and the man door swing first.