Skip to main content

RMC Rate Calculator — IS 10262 BOM Cost + Plant Output Significance

Translating IS 10262 typical mix BOM into ₹/m³ — and the production-side math that tells you whether your plant is mixer-bound or truck-bound.

Why this calc exists

Two questions every RMC plant owner or contractor asks: 'what should I charge per m³?' and 'how many m³ per hour can my plant produce?' The first is a BOM cost arithmetic; the second is a production-rate accounting. They look unrelated but both drive the bottom line — charge too little and you lose money; produce too few m³ and you miss delivery slots.

IS 10262:2019 Annex A gives informative worked examples of typical mix proportions per m³ for M20–M60 — cement, water, sand, CA, w/c. These are not mix-designs (a project-specific mix from a designer supersedes them) but they're a defensible template for cost estimation. The production-rate side is standard cycle-time × fleet-utilisation accounting. The RMC rate calculator handles both, with editable inputs for local unit costs.

Code references (with provenance)

  • IS 10262:2019 — Concrete mix proportioning guidelines. Annex A gives informative worked examples (M20–M60 typical mixes).
  • IS 456 Cl 9 — Mix design requirements (nominal mix M20 or below; design mix above).
  • IS 4926:2003 — Ready-mixed concrete — code of practice (delivery, sampling, transport time limits).
  • GST Schedule II — RMC treated as a composite supply, 18 % GST on delivered price (consult your CA for current rate and ITC treatment).

Worked: M30, Pune, 25 km delivery, 30 % fly ash

BOM: cement 280 kg, fly ash 120 kg, water 160 L, sand 650 kg, CA 1240 kg, admixture 4 kg (1 %).

Material cost (₹/kg): 280×7 + 120×2.5 + 650×1.2 + 1240×1.4 + 4×120 + 160×0.05 = 1960 + 300 + 780 + 1736 + 480 + 8 = ₹5,264/m³ subtotal.

Freight: 25 km × ₹4/km/m³ = ₹100.

Wastage × Profit: ₹5,264 × 1.05 × 1.10 = ₹6,080. + ₹100 = ₹6,180 ex-plant.

GST 18 %: ₹6,180 × 1.18 = ₹7,292 / m³ delivered.

Plant (Tab B): 1 m³ mixer, 90 s cycle, 6 trucks × 10-min round trip → mixer 40 batches/hr vs trucks 36/hr → truck-bound at 36 m³/hr.

Field notes (what trips people up)

  • IS 10262 Annex A is informative. The figures are median crushed-aggregate mixes — MSA 20 mm, 75–100 mm slump, no admixture unless noted. For a specific project, the designer-of-record's mix design supersedes these.
  • Fly ash is cheaper than cement but slower strength gain. The cost saving is real; the schedule impact (longer formwork striking time, later prestress release) is the trade-off. IS 456 Cl 5.2 governs mineral admixtures.
  • GST on RMC is composite. 18 % on the all-in delivered price (Schedule II entry for RMC). Cement input credit (ITC) is generally not available since RMC is the composite supply, but consult your CA for current rules.
  • Mixer-vs-truck bottleneck. The Tab B output tells you which is the limit. Truck-bound → add trucks (cheap). Mixer-bound → need a second mixer or shorter cycle (expensive).

Worked example

Site: small RMC plant in Pune, 1 m³ mixer, 90 s cycle, 6 trucks.

Max output: 36 m³/hr, 288 m³/shift, 7,200 m³/month.

Avg price: ₹7,000/m³ delivered.

Monthly revenue: 7,200 × 7,000 = ₹5.04 cr.

Variable cost: ~₹5,500/m³ (material + freight). Margin: ₹1,500/m³ ≈ 21 %.

FAQ

Why IS 10262 Annex A and not Table 9?

Table 9 is for nominal mix (M5–M20) only. For design mix (M25 and above), IS 10262 governs. Annex A gives typical mix proportions per m³ for cost estimation.

Can I claim ITC on cement?

Generally no, because RMC is a composite supply under GST — the input cement is part of the output composite supply. Consult your CA for current treatment.

What's the typical fleet size for a 1 m³ mixer plant?

Rule of thumb: 5–8 trucks per plant for 25–30 km delivery radius. The bottleneck analysis confirms when more trucks are needed (truck-bound) vs when a second mixer is needed (mixer-bound).

Related reading & tools

  • ../calculators/rmc-rate.html — RMC Rate calculator
  • calc-trial-mix-batch-significance.html — Trial Mix Batch Significance
  • mix-design-masterclass-is10262.html — Mix Design Masterclass — IS 10262
Indicative tool — not a substitute for engineering judgement. Results are computed from formulae and reference values cited to Indian Standards and other published codes as named on this page, using nominal default assumptions; clause and table references are given in good faith for study and preliminary checks. Always verify the current edition and amendments of any cited standard in the BIS catalogue before relying on it. Final mix proportions, structural checks and construction decisions must be confirmed by a qualified engineer against the project design brief, drawings and site conditions. ConcreteInfo accepts no liability for design, procurement or construction decisions taken on the basis of these tools. Code references & rights: Indian Standards are the property of the Bureau of Indian Standards (© BIS) — official PDFs at bis.gov.in. Shared in good faith as technical reference for the civil engineering fraternity — always verify against the official publication.