What is the maximum thickness for an 8-foot-high hollow masonry foundation wall that is 4 feet below finish grade on the exterior?

The correct choice of 8 inches as the maximum thickness for an 8-foot-high hollow masonry foundation wall 4 feet below finish grade is based on structural and building code guidelines. In construction, particularly for masonry foundation walls, the thickness is determined by several factors, including the wall height, the loads it needs to support, and stability considerations.

Typically, the guidelines for masonry walls indicate standard thicknesses based on the wall’s height to ensure adequate strength to resist lateral forces, such as soil pressure and hydrostatic pressure from groundwater. An 8-inch thickness for a foundation wall of this height is common, as it provides sufficient mass and stability to withstand these pressures while also accommodating typical construction practices.

If the wall were to be thicker, it might exceed what is necessary for structural integrity and add unnecessary material cost. Conversely, a thinner wall might not provide the necessary support, leading to potential structural issues. Consequently, 8 inches balances durability and practicality, making it a standard choice for this type of foundation wall in similar conditions.