How Thick Does A Concrete Retaining Wall Really Need To Be?

Concrete retaining walls, which are valued for their strength and versatility, necessitate precise construction methods. This level of technicality comes with a lot of versatility. Poured concrete retaining walls can be colored, textured, and embellished with embedded objects, among other things. Concrete, when properly installed, allows for far more customization than any other retaining wall material.

The proportioning of a retaining wall is just as critical as its structural design when it comes to its construction. Construction-friendly proportions make it easier to lay concrete and leave enough space for structural reinforcement.

What should the thickness of a concrete retaining wall be?

The required minimum reinforcement cover affects wall dimensions (generally member thickness) in addition to basic structural requirements. This can add several inches to the thickness of the wall and varies depending on the severity of the exposure, soil type and reactivity, and so on.

For proper concrete placement, the top of the stem of any cast concrete retaining wall should not be less than 12 inches.

Joints in Concrete Retaining Walls

  • Contraction Joints – Vertical joints or grooves are shaped or cut into the wall to enable the concrete to shrink without causing damage. Contraction joints are usually 0.25 inches wide and 1/2 to 3/4 inch deep, and they are spaced no more than 30 feet apart.
  • Expansion Joints – To account for expansion due to temperature changes, vertical expansion joints are built into the wall. Flexible joint fillers may be used to fill these joints. To link adjacent parts of the wall, greased steel dowels are often cast horizontally into the wall. Expansion joints can be spaced up to 90 feet apart.
  • Construction Joints – There are vertical or horizontal joints that are used to link two concrete pours. Keys are used to improve the joint’s shear resistance. If no keys are used, the first pour’s surface is washed and roughened before the next concrete pour. To give the stem added sliding resistance, keys are almost always formed in the foundation. The stem is built after the foundation has been created.

Size of concrete retaining wall footing

The width of the base slab from the top to the bottom should be held to a minimum of two feet. It should, however, always be below the seasonal frost line, which in northern climates is sometimes much lower.

The length of the base slab is normally between 50 and 70 percent of the wall’s total height (bottom of base to top of stem).

The stem thickness at the base of cantilever and counterfort walls is always around 10% of the total wall height, as is the base slab thickness. Counterfort retaining walls have counterforts spaced at 30 percent to 70 percent of the total wall height from center to center.

A footing key may be used in some cases to increase resistance to sliding. The footing key is an extension of the stem that reaches below the base’s bottom.

Are You Looking for a Company to Build Concrete Retaining Walls for Your Home? 

Spaulding Concrete has been the SF Bay Area’s top Concrete Retaining Wall Builder for over 30 years.  We’re here to build your home’s retaining walls that will last a lifetime, no matter where they need to be placed. We have the specialized equipment, services and professional experience that you need to make permanent improvements to your landscaping. To get you started on the right foot, we would be happy to give you a free quote for your retaining walls. When you reach out by phone or email we will have one of our experts answer any questions you have and explain how we can restore integrity and structural stability to your home or landscape permanently. The qualified concrete experts at Spaulding Concrete will be on schedule, on budget and meet or exceed standards by careful planning, professional execution, and strict quality control. To schedule your free quote, contact us today! We are proud to serve Orinda, Lafayette, Moraga, Pleasant Hill, Concord, Martinez, Pittsburg, Antioch, Brentwood and the surrounding areas.