All About Concrete Gazette Today

Steps To Build Retaining Walls On Slopes

Oct 8


Retaining walls serve as property boundaries, prevent soil erosion, and make it easier to make the most of your landscaping space; retaining walls can add value to residential and commercial properties.


Today, retaining walls create terraced areas that can be planted. You can build flatter areas if your property is situated on a slope. You can build a retaining wall using bricks, pavers, and concrete blocks. Here are some steps to follow if you want to do this DIY project.

How to Build a Retaining Wall at a Slope

The first Step in building a retaining wall on a slope is to make the necessary step-ups for your property. This is the place where the lowest wall height will be constructed.

Each property is unique so a 24-inch base trench will be required. For the required number of blocks or materials, you will need to allow six inches for each foot of wall height.


You can dig a base trench 18 inches wide by four inches deep if your wall is less than four feet tall. Also, the trench must extend far enough into the hill to bury whole blocks. An engineer will usually be needed to finish the initial steps if there is a slope below where the wall begins.


Step 1: Get the Trench Compact & Level

Once you have completed the base trench, you need to level it. This part usually requires a plate compressor. A minimum of two passes is required to get an acceptable result. Sometimes, it may take 4-6 keys to create the foundation. After completing this Step, you can place the drainpipe to the back of your trench at the lowest point.

Step 2: Install the Wall Rock

Place at least 6 inches of wall rock on the base trench. To ensure your project is stable, you must make two passes with the plate compressor after it is leveled and in place.

Step 3: Excavate Second Level

Once the trench is in place, it's time to start building the second level of your wall. This area will need enough space for the buried rocks and base material. Once everything is in place, compact the site and ensure its level.

Step 4: Place the Base Course Of Blocks

Once you have completed the trench and the step-up area, place the base course blocks on top of the base material. To ensure that your work is sturdy and supportive, always check that each addition is level.


It is possible to use concrete blocks to fill hollow cores. After you have completed your building work, the unions and the base for the next step-up level of your home should be equal.

Step #5 - Compact the Wall Rock behind the Blocks

After you have put the blocks in place, the plate compactor will be used to compress the wall rock. This will ensure that the slope supports are correctly in place. Continue this work until you reach the top of your grade. Each block must be completely buried at every step-up level to provide the proper base depth. Erosion can eventually cause wall failure if you don't do this Step.

Step #6 - Fill in the Step Up Areas

Because of the slope, gaps will likely be filled with soil or other landscaping material after you have built the retaining wall. Your goal is to achieve a level, flat result that suits your needs. These materials don't have to be compacted, mainly if you use them for flower beds and other purposes.

Call Pittsburgh retaining wall repair contractor if you have questions about building a retaining wall on slopes for your next commercial or residential landscaping project. We can give you a free estimate to let you know how cost-effective this improvement is.