Handrail heights are measured from the top of the stair tread to the top of the handrail bar.
The height can be no less than 30 inches, but no more than 34 inches high. Determining the height between that is strictly preference.
One Side or Both?
When determining if you need a handrail on just one side or both, consider the width of the staircase. If the width of the steps is less than 44 inches with an open side, just one handrail is needed on the open side. When the width of your staircase is more than 44 inches, but less than 88 inches, place a handrail on both sides of the staircase whether it has open or closed sides. Any staircase that measures more than 88 inches in width requires a handrail on each side as well as a third handrail placed in the center of the steps.
Is a Handrail Needed?
This largely depends on the number of risers in your staircase. If a staircase has only three risers, you do not need a handrail. However, if a staircase has four or more risers, you do need a handrail. With series of staircases, if you split them up and have platforms in between, as long as there are no more than three risers in each series, no handrails are needed.
When mounting a handrail to a wall, remember not to mount it too close to the wall. People need to be able to get an unobstructed grip on the rail. The distance between the handrail and the wall needs to be no less than 3 inches. Another thing to consider is that people should be able to keep a smooth grip on the railing on the top and both sides, meaning that the mounting hardware must attach to the handrail on the bottom. To ensure that the handrail is secure enough, space the mounting hardware no more than 8 feet apart.