Can anyone show me where a folding lower section of the bar counter can't be used as long as it meets the other requirements? This is not for designing a new bar. I often am asked if an existing bar can just add a folding lowered section to meet the 5% and or 60'' rule. Back in the day they were allowed in existing conditions but now removed from the code.

Often a bar top will end or begin at a wall that would allow a perpendicular extension against the wall. Why can't this lowered section be hinged?