Peterson Blog.scape

In This Section

Learn The Basics of a Block Retaining Wall

March 16, 2017

The amount of landscape retaining wall products, designs, and terminology can be intimidating when selecting a retaining wall. It helps to be aware of retaining wall costs, terminology, and construction methods when starting a landscape project. Learn the basics about block retaining walls.

What is a block retaining wall?

Block Retaining WallA segmental retaining wall is a landscape wall made of prefabricated concrete. Also known as a mod-block wall, these Lego-like blocks fit together perfectly to make a uniform wall that is easy to install and repeat. Unlike concrete cinder blocks, a segmental wall doesn’t require mortar or veneer; they can be dry stacked and the surface is already finished.

Block walls are different from boulder, natural stone, and cut stone even though some mod-block walls are designed to look like cut stone. Like any retaining wall, a block wall requires a proper rock base and backfill for support. If the landscape retaining wall exceeds 4 feet in height, a geogrid should be used to reinforce the structure.


SRW – Segmental Retaining Wall more commonly known as block retaining wall
Mod-Block – Modular Block that is prefabricated to fit together
Dry Stack – Block or stone laid without mortar
Course – A horizontal row of block
Batter – The slope of the wall. Each course setback a couple inches so the wall “leans” into the earth
Backfill – A layer of rock behind the wall for structural support and proper drainage
Geogrid – Heavy duty mesh laid horizontally behind the wall for soil stabilization

Types of Retaining Walls

Common Brands

Three of the most common manufacturers of block walls are VERSA-LOK, Anchor, and Belgard. Each company has their own unique designs, colors, and shapes.

VERSA-LOK – Known for their pinned retaining walls, they have been in business since 1987. Their blocks are designed with holes and slots that link together by sliding in plastic pins. Headquartered in Oakdale, Minnesota. Website

Anchor Block – In business since 1909, they introduced landscape products in the late 1980’s. As well as inventing a pinless and mortarless retaining wall, they make pavers, fire kits, and veneers. Headquartered in Minnetonka, Minnesota. Website

 Belgard – In business since 1995, they have a large variety of designs and products for wall block, fire kits, pavers including porcelain. Website

Retaining Wall Cost and Lifespan

The cost of a block retaining wall depends on the size, the design, and what product is used. The material cost could vary as much as $10 per square foot. The overall cost is less than a natural cut stone wall, but less than a boulder retaining wall. A properly installed retaining wall should last a lifetime and require minimal maintenance.