This Retaining Wall Calculator will save time calculating the number of blocks for your new project. If your garden needs landscaping and you do not know how to estimate it, this is an excellent tool for you. 

With the help of this calculator, everything is much simpler, so we hope that this article will be helpful to you. Also, you can check our other calculators, such as Fire Glass calculator or Pool calculator.

Retaining Wall – Definition

A retaining wall is an artificial construction that you can build to retain and maintain the land’s natural slope. You can use a retaining wall to create flat ground or create a more functional space. From the point of view of functionality, retaining walls include absolutely any structure whose basic task is to strengthen the slope, to create terraces, or possibly to prevent the disintegration and destruction of the soil.

Retaining walls are both functional and decorative items. If you look at it from a retaining wall design and aesthetics, they belong to a number of vertical objects and structuring elements. If we consider the last number of years, the decorative role of retaining walls has become very dominant.

Retaining wall drainage is a system of water management. You can build them to control and redirect water flow and stormwater runoff.

Retaining Wall – Formulas

You can calculate the number of retaining wall blocks using the formulas:

\text{Number \;of \; Rows} = \frac {\text{wall\;height}}{\text{block\;height}}
\text{Number \;of \; Columns} = \frac {\text{wall\;length}}{\text{block\;length}}

When you want to calculate the amount of gravel, you can use the following formula:

\text{Backfill Gravel Volume} = \text{Thickness} \times \text{Length} \times \text{Depth}

It is essential to note that the length and height of the wall correspond to the size and depth of the embankment. The thickness should not exceed 30 cm. If you want to calculate the volume of gravel or convert the volume of gravel to the required weight of gravel, see the following formula:

\text{Backfill Weight} = \text{Gravel Density} \times \text{Backfill Volume}

Retaining Wall Estimation Tips

There are various ideas on how you can use retaining walls. You can use retaining walls to provide a flat surface for your garden or landscape by retaining soil, and other materials. This retaining wall element design is often used to create outdoor living spaces. It is important to note that not all retaining walls are made of concrete, but other materials such as stone retaining walls, brick, or gravel blocks-water flow. If you consider building a retaining wall, it is important to understand the different styles and methods.

We distinguish three types of retaining wall: dry, wet, and prefabricated. The time and money you need depend on the type of retaining wall.

  • Dry-stack retaining walls – rocks and other materials do not require mortar. This is the cheapest option, but it is also the most time-consuming and labor-intensive. 
  • Wet-stacked retaining walls – concrete or brick blocks require mortar. These are the most expensive retaining wall types, but they are also the quickest to install.
  • Precast retaining walls – blocks of concrete that are already connected, and they require no mortar. These are the quickest to install, but they are also the most expensive. If you consider building a retaining wall, it is important to understand the different styles and methods. 

Retaining walls are usually installed to control the slope of a sloping property so the cost will depend on the height and width of the wall. To find out how much your retaining wall will cost, there are a few factors you will need to consider. The first thing that needs to be done is to measure the width and length of the wall. It is also necessary to measure the height of the wall. The price of the wall is affected by the height of the wall, so you will need to make sure that you have done everything as required.

Retaining Wall – Table of Pricing

When building a retaining wall, it is necessary to consider all the retaining wall costs. The average price is $20 to $50 per square foot to build a retaining wall. When installing a concrete retaining wall, the average length is 50′ and costs between $4,000 and $10,000.

A retaining wall ranges from $10 to $30 per square foot. It is also important to mention the prices of materials, which vary from 5 to 20 dollars per square meter. Calculate your dimensions with this Wall Square Footage Calculator.

Average retaining wall cost by length
Average retaining wall cost by length

Retaining Wall Calculator – How to Use?

With the help of this retaining wall calculator, you can easily reach your budget. The calculator is easy to use, and now we will explain how.

Calculating the number of retaining wall blocks

It is the first thing you need to do. At the very top of the calculator, you have the option to answer whether your retaining wall will have a row of retaining wall caps, with “yes” or “no.” The highest row of the retaining wall, whose height is higher than the actual one of the walls, is called the row of caps.

Secondly, it is necessary to enter the height and length of the retaining wall. And thirdly, you need to enter the height and length of one of the selected blocks.

Calculating the gravel for backfilling

After the first step, it is necessary to calculate the gravel for backfilling. Wall stability is crucial, and backfilling is necessary to build a retaining wall. When calculating this, it is crucial to know the backfill area’s height, length, and thickness.

Calculating the costs

And the last thing you need to do is calculate the costs. With the help of our calculator, you will quickly calculate the cost of the retaining wall, and you will do this as follows. First, you need to enter the price of one block (considering the block, if you chose this option initially). Then enter the cost of gravel (unit weight). The calculator will show your costs for this project.

Retaining Wall Calculator – Example

The following example will explain how you calculate the required data when building a retaining wall.

Data that you have:

  • project has a cap row,
  • length is 40 feet,
  • height is 15 feet,
  • 15×20 inches of a block,
  • the standard backfill thickness is 15 inches,
  • prices are $7 per block of retaining wall,
  • $3 per pound of gravel

You can enter values in our calculator and get the following results:

  • Number of wall block = 256
  • Number of cap blocks = 32
  • Volume of gravel for backfill = 21,237 m3
  • Total cost = $2016,00

Retaining Wall Calculator – Real-world Usage

With our Retaining Wall Calculator you can estimate the amount of material you need. You can use retaining walls to retain soil, sand, gravel, and other loose materials. The design of retaining walls can be in many different ways.

Many homeowners will need to install a retaining wall to meet the needs of their property. This wall needs to be tall enough to support the soil and wide enough to contain the soil and plants. Calculating the dimensions of the wall can be difficult, so many people will use a retaining wall calculator. Retaining Wall Calculator is a tool that helps homeowners and contractors calculate the height and width of a retaining wall. 


How do you calculate retaining wall?

It is important to calculate retaining wall height and thickness for your project before ordering your materials.
number of rows = wall height / block height
number of columns = wall length / block length

How much does a 10-foot retaining wall cost?

A 10-foot retaining wall can be constructed for around $3,000.

How deep should footings be for a retaining wall?

The depth of footings for a retaining wall depends on the height of the wall. The wall height should be at least the depth of the wall footings below the ground’s surface. For example, if the height of the wall is four feet, the footings should be at least four feet deep.

Why are retaining walls so expensive?

Retaining walls are expensive because they are made of concrete, durable material. They are also often large and can take a lot of time to build. The materials and time it takes to build a retaining wall will determine the cost.

What material do you put behind a retaining wall?

For a retaining wall, you must have a layer of soil or sand behind the wall to help support it. You can also use cement, mortar, or lime.

Should you put fabric behind the retaining wall?

The height of the retaining wall is essential. If you build it higher, you will need to put fabric behind it. The fabric can be used to prevent erosion and water from running down the face of the wall. You can also prevent ice and snow from accumulating on the wall.