How does a ledger board support joists?

A ledger board is a critical component in the structural support of joists, particularly in deck constructions or similar structures where joists need a secure attachment point. This board is typically installed horizontally along a wall or a beam, and its primary function is to provide a stable and sturdy surface for the joists to rest upon.

When a ledger board is fastened to a beam near the bottom, it creates an effective load-bearing connection. The joists are then attached perpendicularly to this ledger board, allowing the weight of the joists and any additional loads (like decking or roofing material) to be transferred directly to the wall or beam through the ledger. This connection helps distribute the load evenly and prevents the joists from moving or settling, ensuring the overall integrity of the structure.

In contrast, other methods, such as embedding in concrete or placing beneath the joists, do not provide the same level of support and attachment for the joists as fastening the ledger board to the beam near the bottom does. Such options may not create the necessary stability for the joists, potentially leading to structural issues.