Does a business have to have a low-clearance sign if there is a low clearance...

[Ashton]

...on the property? I recently rented a U-Haul truck and I made it back to the return place but i went to go under a overpass sort of thing and hit it. Now they are charging me a lot of money. I was just wondering if it is required my the state of North Carolina to have a low-clearance sign if it is low for the biggest truck U-Haul has