Calculator

Retaining Wall Calculator

Calculate the concrete volume required for retaining walls including base slab and stem. Get accurate m³ estimates for retaining wall construction in Zanzibar.

Instant estimate

9.300

1.800 m³ base + 7.500 m³ stem

Wall dimensions: 10m × 2.5m

Stem cross-section area: 0.750

Base: 600mm × 300mm

Recommended grade: C25

Planning estimate only. Confirm structural design before ordering.

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How to Calculate

Retaining Wall Concrete Formula

Base Volume = Length × Base Width × Base Thickness

Stem Volume = Length × Height × Average Stem Width

Calculate the base slab volume first, then the trapezoidal stem volume. For a tapering stem, average the top and bottom widths. Sum both volumes and add 5–10% waste for formwork tolerances.

Base slab

10m × 0.6m × 0.3m = 1.8 m³

Tapered stem

10m × 2.5m × 0.3m avg = 7.5 m³

Drainage

Include weep holes and drainage behind wall.

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Next steps

Need retaining wall concrete supply coordination for your project?

All building materials under one trusted roof — WhatsApp context or upload your BOQ and we coordinate the lines your site actually needs.

Reply within 24h Mon–Sat on structured requests — indicative timing, not a guarantee.

First steps

  1. 1.Share photos, a BOQ or voice notes on WhatsApp
  2. 2.We confirm lines, indicative prices and delivery windows
  3. 3.Materials leave the yard — coordinated to your site