Final answer:
A suitable foundation plan is essential before masonry wall construction to support the wall's weight and ensure stability, requiring engineering assessment.
Step-by-step explanation:
A suitable foundation plan must be established prior to masonry wall construction. This is critical as the foundation supports the weight and ensures the stability of the masonry wall. A properly designed foundation plan considers factors such as soil type, load-bearing requirements, and environmental conditions to prevent settlement and structural failure of the wall. The plan often requires professional engineering assessment and approval before construction begins.