Our Keystone Block Retaining Wall System

Holyoak X in Santaquin, UT offers a full-service keystone block retaining wall system. We give you the full package from start to finish.

We can also do any amount of the work you don't want to. For tall walls we draw plans, prepare them for city approval, acquire city permits. We can also excavate, set the block, and backfill.

How To Install a Retaining Wall

Installing a keystone block retaining wall in your backyard is a process with multiple phases. Because of this, keystone block retaining walls take planning and preparation. The possible phases of installation of a keystone block retaining wall include design, excavation, leveling pad, stacking block, backfill, and final grading. Each step will be explained individually below.

Design of The Keystone Blocks and Wall

Careful consideration should be taken when installing keystone retaining wall. Any retaining wall over 4' tall should be designed by an engineer. When designing the wall elevations of the starting point of the wall and the ending point of the wall at both the base and top of the wall should be measured. It is important to do this to understand what the wall will look like in the end. As a retaining wall is built it is laid perfectly flat. This ensures that the wall is stable. Because the wall is installed flat, if the property has a sideways slope the wall will need to be stepped to account for that.

Once the proper elevations are measured and the steps are designed, the wall construction can move forward. The blocks are ordered per design. There are two types of blocks, a base block and a top block. The base blocks are used throughout the wall and installed by stacking on top of each other. The top block is a flat block placed on top of the last course of blocks as a finishing element to the wall.

Excavation for the Wall

Excavation is the first construction phase of the block wall installation. Care is taken during excavation to not disturb any existing landmarks or objects that will remain post construction. The excavation typically extends about 4 to 6" below the bottom of the first row of blocks to account for the leveling pad that will be installed beneath the block. Typically the retained earth behind the wall must be excavated at a minimum of 1' if the block wall is not an engineered wall to allow for a gravel backfill layer which is discussed later. If the wall is an engineered wall the retained earth behind the wall will need to be excavated the required amount by the engineer ranging from 6 to 15 feet to allow for the installation of geogrid.

Leveling Pad Under the Wall

After excavation is completed the leveling pad is installed. For small retaining walls a leveling pad is typically made from gravel. When walls extend over 100' long the leveling pad is usually made of concrete. The bottom row of block is much harder to lay when the leveling pad is made of gravel versus concrete.

A Keystone Block Retaining Wall We Installed In Santaquin, UT.

Another Wall Installed In Santaquin

Backfill Behing the Block Wall

The first foot of area behind the wall should be gravel to allow for drainage should water collect behind the wall. This prevents possible retaining failure during the winter when ice could form behind the block and force them outward causing the block wall to fall over. At the bottom of the gravel layer a perforated pipe is installed to collect the water moving through the gravel. This pipe drains out the wall. Behind the gravel native material can be used to backfill if necessary. If an engineered wall is built the engineer will specify the type of backfill material to be used.

Final Grading Above the Retaining Wall

After the wall is built and backfilled final grading is done. Dirt is leveled and placed to allow for proper drainage. We can also grade and prep for concrete at this point.

Special Considerations

Permitting for any retaining wall over 4' tall is required in almost any city. This is because a retaining wall should be built to meet modern code requirements and be structurally sound to prevent any harm. Most cities will require a stamped set of plans that an engineer can design and stamp for a relatively low cost to ensure the project is structurally sound.

-Do you have landscaping you want to save? Retaining walls are a messy project with excavators, pallets of block, and gravel backfill. If you want to protect your landscaping around the construction zone, the price will generally go up. The dirt will need to be hauled away and more hand work will be done to install the wall.

-If you are retaining a hill above your property you may need to coordinate with the property owner above you. Retaining walls over 4' tall require a geogrid to be installed behind the wall. If the wall is placed on the property line, the geogrid would be installed on the other property owner's property.

How You Benefit

Installing a retaining wall is a great landscaping choice on a property. Level ground is easier to maintain and is more usable in yards and gardens. A retaining wall will allow for more space and less maintenance. A retaining wall is known to substantially improve the value of a property. Consider also installing a rock wall or large concrete block wall.