For solid masonry, how deep must wall ties be embedded in the mortar bed?

The correct answer is 1.5 inches because this is the standard requirement for wall ties in solid masonry construction. Wall ties are essential components that help to secure the veneer or facade to the structural backing, ensuring proper stability and structural integrity. Embedding the ties at a depth of 1.5 inches into the mortar bed provides sufficient anchorage to resist lateral forces while allowing for proper bonding between the masonry units. This depth ensures that the ties effectively distribute loads and accommodate any expansion or contraction of the materials without compromising the overall design and functionality of the masonry wall system.

In contrast, the other depths listed do not meet the established best practices or building codes for masonry construction. Shallower embedment may not provide the necessary strength or resilience needed for effective structural performance.