Building a deck without a permit could lead to fines for both the homeowner and the contractor. The exact penalties will depend on your state and municipal building laws. You might also be required to remove the deck and apply for a permit before you can build another. While it might be tempting to skip the permit to save a few bucks, it’ll cost you much more if you’re caught.

The overhang, or nosing, of deck steps is another area that will be covered in building code requirements. The noses on your deck steps should have a minimum overhang of ¾ inch. For safety, usability, and code compliance, the nosing of deck steps should not extend past 1¼ inches.

Deck stairs should have at least three stringers rather than two. The recommended minimum width for stairs is 36 inches, and the International Association of Certified Home Inspectors recommends at least three cut stringers to provide sufficient support on wood decking stairs of this width. Generally, stringers should be a maximum of 16 inches apart for wood decking and 12 inches apart for more flexible composite decking.

Building codes for deck railings can vary by location, so it's important to consult your local regulations before construction. Generally, a guardrail is required for any deck that is more than 30 inches above the ground.

For residential properties, the standard minimum height for a deck railing is 36 inches. However, some states and municipalities have stricter requirements; for example, California and Washington mandate railings that are at least 42 inches high. Therefore, a 42-inch railing is not considered too high and may be required in your area or chosen voluntarily for additional safety.

In addition to height requirements, codes also specify other safety features, such as the maximum spacing between balusters to ensure they are close enough to prevent a child from squeezing through.