Like all retaining walls, the purpose of a cantilever retaining wall is to retain loads of sloping soil behind it, providing for level ground in front of it. The L- or inverted T-shaped cantilever wall construction provides the retaining wall with a greater effective mass.
In addition, the weight of the soil and backfill is counteracted by the cantilever retaining wall, preventing slippage or collapse. Some cantilever wall designs also include a key that digs into the ground below, offering even greater stability.
Because of its solid base, a cantilever wall has a relatively thin stem, which requires less space. These walls offer effective solutions for up to 32 feet in height.
A cantilever wall is a complex construction so an engineer must design it. Cantilevers are most often made from reinforced concrete, though this isn’t the only option. Reinforced cinder or concrete block cantilever walls are also popular. If you prefer the natural warm glow of wood, pressure treated wood cantilever walls may suit you better, particularly for shorter walls. Cinder blocks and wood are perfectly good options for retaining walls of 8 feet or less.
How Cantilever Walls Work
The beauty of a cantilever wall is that the footing provides the strength that prevents soil displacement. This is why cantilever walls don’t need any external restraints. Gravity exerts downward pressure on the base, creating an opposing upward pressure with enough force to hold the retained load in place.
A structural engineer will calculate the forces and the required retaining wall dimensions. To do this they will consider the following factors:
- Water runoff and drainage requirements
- Type of soil
- Prevailing climate
- The presence of seismic activity
- Underground facilities like sewage and cables
- Structures and amenities on either side of the wall
- Building Regulations
Beautiful Cantilever Retaining Walls
Many property owners have come to appreciate the beauty of retaining walls. Apart from leveling the ground and making flat space available, retaining walls can take on any shape or form.
Steps and seating space are often included in the construction. Veneers and colored paint or stucco can offer aesthetic opportunities to match the wall appearance to other nearby structures, or blend them with the surroundings.
You’ll add value to your property when you install a cantilever retaining wall, whether you choose to build with reinforced concrete, blocks, or pressure treated wood.