Our coach is 12'2" high. Here we are on a turnout on the Natchez Trace a few years back: Oopsie!
Time to unhook and back out.
That's why we have our motor home's height, width, and weight, in both English and metric, on labels right above the speedometer. When driving in Canada and Mexico, it's heart-thumping to see a sign like "Height Limit 3.6 Meters Ahead," or "Weight Limit 16 KG" on a bridge. Quick! What's that? How tall are we?! How much do we weigh?!