Building stairs that comply with safety standards requires not only that you apply local code standards to constructed stair rails heights, but also to constructed stair post heights.
Rail and Post Height Codes
Although there is an international residential code for handrail heights (34 to 38 inches) local codes may require sizes that are different from those of the international code. Sizes for handrails, both balusters, and newels, must also conform to these codes.
A baluster, sometimes referred to as a stair stick or banister, is one of a group of mounted vertical shafts, or posts, that support a stair handrail. Some of these balusters are molded. Others are turned on a lathe. But all must conform to local codes. Pre-manufactured balusters whose height fails to conform to local codes can often be re-sized to conform.
The vertical post supporting a handrail at the foot of a staircase is referred to as a "newel." These posts can also be used as intermediate support on a stair landing and at the top of the staircase. Most newels are three to three and a half feet in height. Box newels, though, are typically five to five and a half feet tall.