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.

The average cost to professionally clean or pressure wash a deck is around $150, with prices typically ranging from $100 to $600. Several factors influence the final price, including the deck's size, material, condition, and how long it has been since its last cleaning. For a smaller deck of about 300 square feet, you might pay around $100. For a larger deck of 1,000 square feet or more, the cost could be closer to $300 to $400. Decks that are very dirty or haven't been cleaned in years may require more time and special detergents, which will increase the price. The deck's material also plays a role. Wood decks often cost more to clean because they require a gentle power washing technique to avoid damage. Composite decks are typically less expensive to clean, and cleaning a metal deck may cost around $100.

It depends on the type of wood. The average cost to build a deck out of pressure-treated lumber is $15 to $25 per square foot, but more affordable varieties such as bamboo and cedar cost less at around $3 to $10 per square foot. However, when comparing the cost of vinyl decking versus wood decking, it’s important to also consider ongoing maintenance costs. For example, most woods require regular sealing to keep them protected against weather and rot.

The cost to build a second-story deck averages $4,800, though the actual price could range as low as $420 to upwards of $16,000. While labor costs range between 35% and 50% of the total project cost, the materials and complexity of design will ultimately lead you to save or spend more money on this home addition.