How does proper backfilling and drainage around foundation walls influence masonry performance?

• A. It prevents water accumulation and reduces soil movement pressures on the wall, improving durability.
• B. It increases hydrostatic pressure on the wall.
• C. It has no effect on masonry performance.
• D. It increases moisture infiltration.

Answer: (A)

Proper backfilling and drainage around foundation walls control the water and soil forces that the wall has to resist. When backfill is placed correctly and a drainage system or layer is used to carry water away from the wall, water does not sit against the foundation. That lowers hydrostatic pressure against the wall and reduces soil movement pressures, keeping the masonry under less stress. In drier, better-drained conditions, mortar and units are less prone to cracking, moisture-related deterioration, and freeze-thaw damage, so the masonry lasts longer and performs more reliably.

If drainage is poor and the wall is in contact with saturated soil, hydrostatic pressure increases, moisture can infiltrate the masonry, and deterioration accelerates, which is why the other options don’t fit.