How is the load-bearing capacity of a deck determined under the IRC?

The load-bearing capacity of a deck is primarily determined by several critical factors, including the materials used in its construction, its configuration, and compliance with local code requirements.

Materials play a significant role because different types of wood, composites, and metals have varying strength characteristics and load capacities. For instance, pressure-treated lumber often has a different load-bearing capability compared to cedar or redwood.

The configuration of the deck, such as its design, size, and how it’s supported, also impacts its ability to handle weight. Decks that are cantilevered or that have specific spans between supports will require careful structural design to ensure they can bear intended loads without failure.

Additionally, local code requirements provide guidelines that reflect environmental conditions, potential loads (like snow or wind), and safety standards that must be adhered to during the design and construction process. These codes are structured to ensure that decks are safe for use and can support the expected loads.

Therefore, the combination of the materials chosen, the structural configuration, and adherence to local regulations collectively defines how much weight the deck can safely carry.