Gabion Wall Calculator — Baskets, Stone & Membrane

This calculator determines the number of gabion baskets, fill stone weight, geotextile membrane and connectors needed for your gabion wall.

Basket quantities

Baskets along length = ceil(Wall Length ÷ Basket Length)
Baskets in height = ceil(Wall Height ÷ Basket Height)
Total baskets = Baskets Long × Baskets High
(single-skin wall, 1 basket deep)

Fill stone

In-cage volume (m³) = Number of baskets × Basket volume
Fill weight (tonnes) = In-cage volume × Bulk density

Bulk density already allows for the voids between stones, so suppliers sell gabion stone by the tonne — that tonnage is your order figure. The typical UK supplier figures below are indicative; always confirm against your chosen supplier.

• Cobbles (rounded): ~1.8-1.9 tonnes per m³
• Limestone: ~1.7 tonnes per m³
• Granite stone / Recycled concrete / Sandstone: ~1.6 tonnes per m³

Accessories

Geotextile membrane is placed behind the wall to prevent soil migration through the stone. The membrane figure is a rough area allowance — where sheets join, specify a minimum physical overlap of 0.6m at horizontal and vertical joins. Spiral (helical) connectors are 1m preformed wires that lace adjacent panels and baskets together along each joint; the connector count is an installation-guide estimate, not a manufacturer per-basket rule. Stiffener / bracing wires hold the face flat while filling — install guidance braces a 1m cell at about 1/3 and 2/3 fill height (≈2-3 ties per cell). Confirm all accessory quantities against your gabion supplier. For aggregate quantities, also see our Aggregate Calculator.