Frequently Asked Questions

The International Residential Code (IRC) requires that gaps between balusters must not allow a 4-inch sphere to pass through. On stair railings, because of the angle, the maximum opening is 4-3/8 inches. A practical rule of thumb is to place approximately three balusters per linear foot of railing to comfortably meet this requirement. Always confirm with your local building department, as some jurisdictions adopt amendments to the model code.