How do you build a gabion wall or fence?

A gabion is essentially a heavy-duty wire mesh. It is a steel mesh (also known as a grid) that is treated to withstand the more demanding pressures from its contents and elements.

At one time, gabions were made of lightweight wicker. It wasn't perfect, but it was innovative and effective. Today, gabions are made of tougher materials, giving them greater strength and longevity.

How do you build a gabion fence?

Step 1 - Laying out the site

Begin by laying out the wall using a string and line level or a carpenter's level mounted on a long straight edge (usually 2 "x4" - 12' long) and check that the mat is level in both directions.

Step 2 - Provide a firm and level foundation

Use a hoe or flat shovel to remove any grass, weeds or topsoil. If the soil is hard, you can place the gabion wall directly on top of the existing soil. If you have sandy or clayey soil, you will need to replace it with compacted gravel or concrete footings about 6 inches deep, otherwise the soil may collapse under heavy pressure. If you do not plan to plant on the wall, use a brush killer (Round Up ) to destroy any weeds or roots, then cover with geotextile.

Step 3 - Gabion Reinforcement - Installing Support Posts

Narrow gabion walls with metal wires have little to no structural integrity. These walls will require internal support columns embedded in concrete and spaced on appx. 6' centers. (See example below)

Depending on installation and local codes, typical posts may be galvanized pipe, pressure treated wood posts, or structural steel members.

Be sure to bury the posts 3-4 feet deep, add dry mix concrete, then wet them and return and begin installation within a day or two.

Step 4 - Assemble the gabion basket

Begin by unrolling and laying the wire mesh panels so that the bottom panel rests flat on the prepared base, by sliding the gabion onto the internal support posts. Our baskets are held together with galvanized steel spirals that you wrap around the adjacent edges of the mesh panels. This is easy to do because the spiral matches the grid spacing of the gabions. When the spiral reaches the end, clamp each end with pliers to hold it in place and prevent it from slipping out.

Six-foot baskets are the most common size. They have a center divider to reduce expansion and are attached along its bottom edge when the cage is open in a flat area, then down each vertical side after the sides are raised and the basket is in place. Depending on the height of the basket, baskets usually require 1/3 and 2/3 support ties at each corner where these baskets are positioned and clamped.

Step 5 - Filling the gabion baskets

If you have available native rock, filling with these on-site materials will produce a gabion wall that fits well into its surrounding landscape.

To prevent spillage, the exterior rock placed on the exposed surface needs to be slightly larger than the grid opening. A typical 3" x 3" grid requires a minimum of 4" of rock, and limits the largest rock to 8". Use angled rocks for the corners, smaller rocks or used brick and concrete materials can be inserted into the center of the structure as they will not be visible when finished.

Packing rocks carefully takes time, but it's important!

Work in layers, using small pieces to fill any gaps and wedge the best looking rocks into the surface of the basket. Orient them as close as possible, then fill in the back to hold them in place.

Step 6 - Adding layers

To get a fence height higher than 3', you usually stack multiple baskets on top of each other. After packing the lower basket, cover its lid with wire and assemble the second layer on top. Fill the second layer as you did the first, using the rocks with the best looking faces and the less attractive filler rocks in the center.