Here are some general rules regarding stair and handrail safety in residential construction. The Photo on the left was taken of a home built in 1978 in Aurora Colorado during a home inspection by my company, Magpie Property Inspections. It shows spacing between the railing spindles well over four inches which presents a safety hazard, particularly for small children. The photo on the right was taken in Parker Colorado during a home inspection of a new home with stairs and railing built to be consistent current requirements.
By today’s standards, balusters (spindles) at decks and steps should be spaced no more than 4″ apart. Standards and rails should be configured so that a hand may easily grasp around a rail for safety. Handrail should be installed at a height of no less than 34″ and no higher than 38″. Stair riser height should not be over 7 3/4 inches , but at least 4 inches. Treads should be at least 8 inches deep. Railing missing at interior and exterior steps should be installed for safety where three or more steps are present.
For outside decks, railings are not required with drop-offs less than 30 inches above grade but we recommend considering your own personal needs and those of your family and guests, and install railing as needed to ensure their safety.