Regulations for Railings on Porches

IRC Height Regulations

• The International Residential Code requires a porch with a foundation 30 inches above ground to contain a safety railing of 36 inches or higher. The IRC code is widely accepted, but it is up to the builder to determine whether local governments require more strict dimensions.

Baluster and Slat Width Regulations

• The International Residential Code requires slats or balusters to be spaced no more than 4 inches apart. Railing designs that create the capacity to climb are prohibited. Local governments may have more strict standards that require research by the builder.

Other Considerations

• The IRC requires the tops of railings to sustain an applied weight of 200 pounds on any section. Slats or balusters must sustain an applied weight of 50 pounds in a square foot area. Railings that run alongside stairs adjacent to a porch must have a minimum height of 34 inches, but it would be efficient for the builder to match the height of stair-side railings to that of the main railing.