Most building codes require that railing spindles (also known as balusters) on decks or stairs be spaced no more than four inches apart. This safety standard is often called the '4-inch sphere rule,' which means a sphere with a 4-inch diameter should not be able to pass through the opening between balusters. This rule is in place to prevent small children and pets from slipping through the railing. For the same reason, the space between the bottom rail and the deck or floor surface should also be no more than four inches. As a general guideline, professionals often install three balusters per foot of railing. However, since specific requirements can vary by location, it is essential to check your local building codes to ensure compliance before starting your project.

For a 12x20-foot (240-square-foot) deck, you can expect to pay between $7,200 and $14,400. This cost is based on a general price of $30 to $60 per square foot. The final price will depend on factors such as the decking material, design complexity, deck type, location, and local labor costs. Keep in mind that add-ons will increase the total; for example, adding an under-deck drainage system to a deck of this size could cost an additional $7,700.

What goes under your floating deck depends on your preferences. Some homeowners put landscaping fabric underneath their decks to prevent weeds from popping up through the boards. Others choose to build a floating deck over grass or gravel. However, it’s best not to set your deck directly on the ground. Instead, set your deck on blocks to keep it elevated enough to prevent moisture from rotting the wood.

The proper and most comfortable height for a deck stair riser, also called a step, is between four and seven inches. A height of seven inches is often considered ideal for a strain-free step that minimizes the risk of trips and falls. While it is possible to have risers up to 12 inches, this height can be challenging for children, pets, or individuals with mobility issues. For optimal safety and comfort, pair a seven-inch riser with a tread depth (or run) of at least 10 to 12 inches. Always check your local building codes, as they may have specific requirements that differ from these general recommendations.