Get matched with top deck maintenance specialists in Martin, TN

Composite decking requires a solid foundation, substructure, or subframe to ensure stability. This base is typically composed of posts, beams, joists, and footings. The frame's joists can be built from various materials like composite, plastic, timber, or metal, as long as the base can support the deck's weight without shifting. A professional deck builder might recommend installing the frame on a solid concrete base for added durability. The final design and materials for the substructure will depend on your budget, the type of deck, and environmental conditions.

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.

Expect to spend around $10,000 to $11,000 to replace a 20-by-20-foot deck. Using high-end materials like composite or exotic hardwoods can drive up the cost, as can custom features and design elements. You can also expect to pay more than average if your deck replacement requires a site evaluation or if you need the work done during the busy season.

Whether you need a permit depends on the deck design and local regulations. Most areas mandate a building permit if the deck is over a specific height or if it's attached to a pre-existing structure. Shorter, freestanding decks may not require a permit, but you should check with local zoning ordinances and your homeowners association for specifics.