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 m³
1.800 m³ base + 7.500 m³ stem
Wall dimensions: 10m × 2.5m
Stem cross-section area: 0.750 m²
Base: 600mm × 300mm
Recommended grade: C25
Planning estimate only. Confirm structural design before ordering.
Get WhatsApp QuoteHow 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.Share photos, a BOQ or voice notes on WhatsApp
- 2.We confirm lines, indicative prices and delivery windows
- 3.Materials leave the yard — coordinated to your site