Rebar Cost Calculator
Material, fabrication, fixing and the all-in cost per tonne.
Inputs
Result
Formula
| Tonnage with waste | total × (1 + waste%) |
| Material | tonnage × price |
| Fabrication | tonnage × rate |
| Labour | tonnage × fixing rate |
| Total | material + fabrication + labour |
| All-in per tonne | total ÷ tonnage |
100 t of rebar at 4200, fabrication 350, fixing 800 and 3% waste: 103.00 t, 432,600 in material, 36,100 fabrication and 82,400 labour — 551,100 in total, or 5350 per tonne.
FAQ
Why does fixing cost so much more than fabrication?
Because fixing is manual, and output depends on complexity and access. A gang fixes 0.6-0.8 t a day on slab steel but only 0.3 t at congested beam-column nodes — 600-1000 per tonne. Fabrication can be mechanised and centralised down to about 300. The way to save is more off-site work, not squeezing the fixing rate.
Is factory-cut bar actually cheaper?
On repetitive floors it clearly is. Site fabrication wastes 3-5% against 1-2% for factory bar, so 1000 t saves 20-30 t of steel — 80,000-130,000 at 4200 — which covers the delivery premium. Projects with many irregular members or frequent changes are the wrong fit, because cut bar cannot be re-cut, and a change turns it into scrap.
How do you fix the rebar price?
Three routes: a contractual adjustment clause tied to the published monthly average for the size, adjusted beyond ±5%; a fixed-price purchase, which ties up cash and carries downside risk; or an annual framework with a mill or major trader, trading volume commitment for a better rate. The adjustment clause is the usual compromise.
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Results are estimating aids only and are not a design basis. Construction and final accounts must follow the drawings, the applicable standards and an approved method statement. Anything affecting structural safety, shoring or falsework must be checked by a suitably qualified engineer.