Recommended Spacing for Porch Railings

Adhering to Building Codes

• For safety, building codes dictate the spacing for balustrades for porch railings. If you hired a professional contractor from your area, he will probably be familiar with local building code requirements. If you are installing the porch railing yourself, contact the building inspector in your town to find out the required railing height and spindle spacing requirements.

Applying Building Codes

• In some situations, building codes may not apply. If your home is a registered historical property, you may be “grandfathered in” and you will be allowed to remodel according to the original specifications. Also, for spaces deemed inaccessible, like dormer windows, you may not have to meet building code requirements. For these areas, railings are decorative and therefore do not have to meet the requirements of usable railings.

Railing Height

• Building codes vary from locale to locale. Typically, common building codes require a minimum of 36 inches from the porch floor to the top of the railing. For porches that are 8 inches above ground level or more, a 42-inch-high railing may be required.

Spindle Spacing

• A baluster is the upright post supporting the handrail, often in a turned design and called a spindle. Building codes regulate the spacing of spindles supporting porch railings, but some general rules apply. Typically, the spacing of spindles and balusters is a maximum of 4 inches between spindles at the narrowest point. Figuring out the spacing for porch railing spindles will dictate how many spindles to buy.

  Generally, a 4- by 4-inch spindle will be spaced 6 inches on center; 3- by 3-inch spindles will be spaced 5 inches on center; and 2- by 2-inch spindles will be spaced 4 inches on center. The space left at each end should be the same size or smaller than the gap between spindles. To space spindles out properly, use a spacing block.