Common building codes for decks include that the deck be 30 inches above grade, which is the ground level directly adjoining the deck, and guard rails are secure and cannot collapse, states About.com. Balusters, or vertical posts, must be built to prevent people from falling off the deck.Continue Reading
Balusters must be 4 inches apart or less, explains About.com. When building stairs, tread, the flat part of the step, must be at least 10 inches from front to back, and maximum rise, the vertical distance from one stair to another, can be no greater than 7 1/4 inches high. A guard rail is required to sustain 2 1/2 times the minimum force, which is 200 pounds; therefore, a guard rail needs to support 500 pounds of force.
The general maximum distance allowed for post spacing is 6 inches apart, allowing the guard rails to sustain heavy force, according to About.com. The cantilever of the deck can usually be no greater than 24 inches in maximum length. Guards must be installed behind benches on decks but are not required to be higher than any other guards installed. Decks need to be built solidly due to the punishment they receive from the elements.
These are general requirements for decks established by the International Building Code. State and local requirements may differ.Learn more about Law