Key takeaways
- Water pressure is the main cause of failure.
- A buried base course and compacted footing are essential.
- Taller walls need engineering.
- Geogrid reinforces walls where needed.
What a wall is fighting
Soil is heavy, and wet soil is heavier. Water builds pressure behind a wall, and clay holds water. A wall without drainage is a dam.
The parts of a good wall
A level, compacted base; a buried first course; clean crushed stone behind the wall; a perforated drain pipe that outlets to daylight; and geogrid reinforcement where height or loads require it.
When you need an engineer
Walls taller than about four feet, walls supporting a driveway or structure, and walls on steep slopes typically need engineering. Rules vary by city, so confirm early.
Signs of trouble
Leaning, bulging, cracks, gaps between blocks and soil staining on the face point to drainage or footing problems. Address them early.
Terraces beat one tall wall
Several shorter walls with drainage between often cost less and perform better than one tall wall.
Related services
Ready for a firm answer on your own yard? Try the Backyard Planner or call 615-431-3789 for a free design visit.