Retaining Wall Companies
A Free Retaining Wall Info Source
  • Local Builders
  • Local Engineers
  • County & City Regulations
  • Block Manufacturers

Modular Block Retaining Walls

Made from pre-engineered concrete forms, modular block retaining wall systems combine durability and affordability. Rows of modular blocks and caps are used to create new and replacement retaining walls. Available in many colors, styles, sizes and shapes, concrete modular block will blend into just about any environment.

modular block example
modular cap example

The modular block used for retaining walls over three feet in height should have a heavy-duty rating by the manufacturer and each block should weigh at least sixty pounds. Modular block can also incorporate attractive steps and stairways that are either rounded or squared in design. Reputable companies will deliver a sample block and cap for your approval.

modular block retaining wall

If built correctly, modular block retaining wall systems are very stable and long lasting; however, that is only if they are built correctly! The simple fact is, hundreds of residential and commercial modular block retaining walls are not being built correctly and failure rates are rising as a result.

Avoid disasters by requesting at least three quotes by reputable retaining wall companies. Verify each has been building retaining walls for at least ten years in your area, are licensed and insured, and provides references unsolicited with their estimate.

When you have made your choice, request a COI (certificate of insurance) and confirm the name of the company matches. The COI will verify that you are a “certificate holder” should anything go wrong during the construction of your retaining wall.

Retaining Wall Height Restrictions

Check your local city hall or county courthouse for modular block retaining wall building height restrictions. Be sure to verify whether an engineer’s plan is required to obtain the necessary building permits.


Call the county or city engineering department to verify the building codes and requirements before signing an agreement with a contractor. If the contractor fails to apply for a building permit or acquires one with incorrect or invalid information, you will receive a stop-work-order and a costly fine.

If a plan prepared by a civil or structural engineer is required to apply for the building permit, be sure the retaining wall company you hire has such an engineer on staff. If they do not, a local engineer must be engaged who will conduct site visits at your property before, during and after the project is complete. As these ongoing site visits add up, it costs less in the long run to hire a retaining wall company with its own engineer. Professional retaining wall builders will also schedule their own engineer’s site visits to coincide with the building steps so progress never stops. Consider these points carefully when comparing estimates.

At the completion of the retaining wall construction project, an engineer’s letter with a stamp should be produced with the property address of your new wall. Keep the engineer’s letter handy should you sell your property as it will add value.

modular block retaining wall with steps

Modular block retaining wall construction plans should include soil reinforcement measures and water management systems which reduce damaging hydrostatic pressure and extend the life of the retaining wall.

Modular block is designed to be porous, which means water will penetrate it; while this adds to the strength of the wall, it also means the block will likely become stained over time from effervescence, mold and mildew. Concrete block retaining walls in moist environments, like the south for instance, are especially vulnerable to staining. If your new or replacement retaining wall will be visible on a daily basis you may prefer a concrete masonry retaining wall.