Gary RV_Wizard
Site Team
Then that is your answer. But what are you going to do when you encounter a "low bridge" on your route? Are you prepared to find a turn-around and backtrack miles to an alternate route?I would be too chicken to go under less than 14 feet, in my 12' 6" RV unless I could do it at less than 2 MPH.
Be aware that most highways in the eastern US were constructed when 13'6" was the standard height. Even on interstates. Also that many old highways were granted exceptions for existing low railroad crossings that were impractical to replace.
BTW, the height shown on underpass signs is the lowest point over the pavement. In most cases, there is additional room at either the center (arch openings) or one side (slanted openings).