Box Gabion

What Is a Box Gabion and Where Is It Used?

A box gabion is a rectangular stone-fill cage made from 3 mm galvanized wire with an 8x10 cm mesh aperture. It arrives on site empty and folded flat, is opened out and laced together in position, and is then filled with crushed stone. Once filled, the resulting structure is a flexible mass that resists by its own weight; it is not rigid like reinforced concrete, and where the ground settles it adapts by deforming slightly instead of cracking.

Common applications include retaining and earth-holding walls, protection of slopes and embankment toes, erosion control along streams and channels, terrace walls in gardens with a change of level, boundary treatments to car parks and roadsides, landscape walls and separating masses in industrial facilities. Being free-draining is the gabion's greatest advantage: water pressure does not build up behind it, which removes the most common cause of failure in earth-retaining structures.

Choosing the Size: 100x100x50, 200x100x50 and 200x100x100

All three sizes have the same wire and mesh specification; the choice is governed by the height and thickness of the wall and by the room to manoeuvre on site. 100x100x50 cm is the size for short runs with changes of direction. On corners, curves, stepped arrangements, seating and landscape details, the smaller the unit the more easily the line takes shape; and as it is the lightest mass when filled, it makes working in confined areas easier.

200x100x50 cm is the standard choice for long, straight runs. Fewer cages have to be laced per metre, which shortens both the labour and the lacing time. 200x100x100 cm is the size for locations where depth of body is required: the bottom course of high walls, banks and stream edges exposed to flowing water, and retaining applications with significant earth pressure behind them. As a rule, the higher a gabion wall goes the wider its base must be; on walls of two courses and above, building the bottom course 100 cm deep and stepping the upper courses back to 50 cm is a sound solution.

Technical Specifications

How Many Cages and How Many Tonnes of Stone? A Worked Example

Two calculations are involved. Number of cages: quantity = wall length / cage length x number of courses. Quantity of stone: volume (m³) = length x height x thickness, then stone weight = volume x approximately 1.5 tonnes/m³. That factor varies between roughly 1.4 and 1.6 tonnes/m³ depending on the type of stone and the void ratio; confirming it with the quarry avoids an ordering error.

Example: a garden retaining wall is to be built 10 metres long, 1 metre high and 50 cm thick. If the 200x100x50 size is chosen, the quantity = 10 / 2 = 5 cages. Volume = 10 x 1 x 0.5 = 5 m³, and the stone requirement is 5 x 1.5 = approximately 7.5 tonnes.

Had the same wall been 2 metres high, the base would have to be widened: 5 units of 200x100x100 for the bottom course and 5 units of 200x100x50 for the top course, 10 cages in total. In that case volume = (10 x 1 x 1) + (10 x 1 x 0.5) = 15 m³ and the stone requirement is approximately 22.5 tonnes. On runs with corners and curves, filling the remaining gaps with 100x100x50 units reduces the need for cutting.

Choosing the Fill Stone and Filling Technique

Because the mesh aperture is 8x10 cm, the smallest dimension of the fill stone must be larger than that opening; in practice crushed stone in the 10-20 cm range is ideal. Smaller stone falls out through the mesh, while very large stone leaves big voids and reduces the weight of the mass. The stone should be hard, frost-resistant and not prone to breaking down; soft stone that disintegrates in water will settle within a few seasons.

When filling, the visible faces are hand-packed and the interior is tipped in. Hand-packing is not just a matter of appearance; a tightly packed front face also stops the wire from bulging under the pressure of the stone. A cage is not filled to the brim in one go: it is filled in lifts of about one third of its height, with internal bracing wires tying the opposing faces together at each lift. Skip these braces and the wall will belly outwards over time.

Installation Steps

1. Level and compact the ground. A gabion does not need a foundation, but it does need a true base that will not settle; on soft ground a thin blinding layer of crushed stone is laid.
2. Open out the cages, lift the side panels and lace the corners with a spiral of galvanized wire; the lacing pitch should not exceed 10-15 cm.
3. Lace adjacent cages to one another in the same way; boxes standing separately are not a wall, they are a row of baskets.
4. Start filling with the front face hand-packed, and fit the internal braces at every one-third lift.
5. Fill the top level without overfilling, then close the lid and lace it along the edges.
6. On high walls, place drainage material behind the structure and a geotextile where required; this layer stops fine soil from washing through the mesh.
7. Check the level and alignment of the bottom course before moving on to the second; an error is corrected in the bottom course, never in the one above.

Gabion, Reinforced Concrete or Fence?

The gabion is the answer for jobs that involve retaining earth and require mass. Compared with a reinforced concrete retaining wall it needs no formwork, no steel and no curing time; it is free-draining, does not allow pressure to build behind it, and adapts rather than cracks when the ground settles. On the other hand, significant heights and loads requiring engineering calculation must be designed properly; it does not replace a reinforced concrete solution built with rebar in every situation.

If all you want is to mark a boundary and control entry and exit, a gabion is an expensive way to do it; panel fence is both faster and more economical for that job. And on non-load-bearing boundary and landscape applications where a wall thickness of around 30 cm is sufficient, a mattress gabion uses less stone and closes the line more quickly. The order of decisions is this: will it carry load, how high will it be, and is there water behind it.

Galvanizing, Service Life, Maintenance and Wrong Choices

Two things determine the life of the cages: the coating and correct installation. The galvanized coating delays corrosion with its layer of zinc; where water runs constantly, or salt and chemical attack are present, more frequent inspection is needed. Once a year, look over the lacing points, the lid ties and any bulging on the front face; tightening a slack tie is far easier than repairing a face that has already opened up.

The three most common consequences of a wrong choice are these: using stone smaller than the mesh aperture causes the fill to spill and the mass to weaken; filling without fitting internal braces makes the wall belly outwards; and failing to widen the base on a high wall creates a risk of overturning. All three are application errors rather than material faults, and all three can be prevented at no cost during installation.

What Sets the Price, and How Do Delivery and Site Surveys Work?

With box gabions the price is driven by cage size, wire diameter, galvanized coating weight, order quantity and the current cost of steel raw material. Building the same run in larger units reduces the lacing labour, while smaller units cut waste on shaped runs; the balance between the two determines the total cost. All the amounts shown in the price table on this page include VAT, and the fill stone is not included in the price.

Our company is based in Ostim, Ankara; we sell the product and ship throughout Türkiye, and because the cages are dispatched folded flat the transport volume is low. Delivery is always charged; the freight cost is added to the order separately, including on deliveries within Ankara. On projects within Ankara the site survey is free: we measure the run and set out the number of cages and the stone requirement in writing. Installation is not a standard service; our teams attend site only on projects with a run of approximately 1000 metres and above.