Skateboarding question?i need an experienced skateboarder to answer this?a skater who has experienced handrai?

how high do you need to be able to ollie over a handrail over a stair?what i mean is handrails are in the middle of the stair set,right.and i want to start out ollieng the stair and then over the handrail and then the remaining of the stair case.how high of an ollie do i need for that?i can ollie about almost 5 boards stacked which is 2 feet and 6 inches.is that high enough?