Anyone use a laser measure to measure height or clearance?

I climb the rear ladder and eyeball it.

Did find a RailRoad overpass marked 13 ft which is enough for my 5th wheel to clear. Something didn't feel right so I stopped short of the bridge, got up on the ladder and sure enough there was a steel girder and a pipe hanging down low enough it would have taken out my A/C unit. Upon closer inspection it looked like a truck had hit the bridge and knocked the girder loose. The pipe was for a light that also had been knocked loose.