Rebar Cost Calculator
Material, fabrication, fixing and the all-in cost per tonne.
Quick answer
With the default inputs: Rebar tonnage 100 · Rebar price 4200 CNY/t · Fabrication 350 CNY/t etc.Total rebar cost 55.10 10k CNY
Edit the inputs below to recalculate.Inputs
Result
Total rebar cost
55.1010k CNY
| Tonnage with waste | 103.00t |
| Material | 43.2610k CNY |
| Fabrication | 3.6010k CNY |
| Fixing labour | 8.2410k CNY |
| All-in per tonne | 5350CNY/t |
| Material share | 78.5% |
| Labour and fabrication share | 21.5% |
| Cost of waste | 1.6010k CNY |
| All-in per 100 t | 53.5010k CNY |
Rebar is the most volatile major material, with 500 per tonne swings within a month, so quotes need a price adjustment clause — usually tied to the published average for the size, adjusted beyond ±5%. Site fabrication wastes 3-5%, while factory-cut and bent bar cuts that to 1-2%, and the saved steel often pays the delivery premium.
Reverse: known result, work out one input
Enter a target result; the other inputs stay fixed and this one is worked out.
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.
How to work it out
- Break the total tonnage down by bar size and grade (HRB400 by diameter) first. Unit price and fabrication cost differ by size, and averaging across them distorts the result.
- Compute the quantity including waste: Q = tonnage × (1 + waste). Waste covers offcuts, lap lengths and accessory bars such as spacers and ladder bars — normally 3-5%, at the top of the range for complex geometry.
- Material cost = Q × unit price. HRB400 rebar commonly runs 3800-4500 CNY/t, with coiled and wire rod slightly higher and plain round bar slightly lower.
- Fabrication = Q × fabrication rate, typically 300-450 CNY/t covering straightening, cutting, bending and thread cutting for couplers.
- Fixing labour = Q × fixing rate, typically 700-1000 CNY/t, at the top of the range for basements and congested joints.
- Total = material + fabrication + labour; the all-in rate per tonne is that total divided by Q, which is the figure to compare against subcontract quotations.
Where it goes wrong
- Allowing 2% waste. Accessory bars — spacers, ladder bars, positioners — are often outside the drawn quantity and add 2-4% on their own, before offcuts. Three percent is a floor, not a ceiling.
- Comparing material price only. A 100 CNY/t difference in material is trivial next to fabrication ranging 300-450 and labour 700-1000; those two drive most of the spread between quotes.
- Estimating tonnage from floor area times a steel-content index and settling on it. Indices (45-65 kg/m² for residential, 100-150 for basements) are for feasibility only; settlement must follow bar schedules.
- Ignoring stock lengths and laps. With 9 m stock, column and beam main bars inevitably lap at 35d-40d per the code, and that steel is routinely missing from budgets.
Material and cost
HRB400 rebar runs 3800-4500 CNY/t and moves with futures — 500 CNY swings between quarters are common. Fabrication 300-450 CNY/t, fixing labour 700-1000. The all-in rate typically lands at 5000-6000 CNY/t. Formwork, concrete and plant are separate.
On site
- With steel this volatile, large projects often use a price-linkage clause tied to the published mill price on the order date. Fix the reference date and the adjustment formula at contract stage.
- Check whether the fabrication rate includes couplers and thread rolling. Mechanical couplers save steel against lapping but cost more to fabricate, so cost each joint type separately.
- Scrap recovery offsets part of the cost, and good bar-schedule optimisation typically saves 1-2% of steel — more effective than haggling on price.
- Any substitution on site, larger for smaller or equal-grade swap, needs design approval. Equal strength is not enough: anchorage, crack control and seismic detailing all have to be checked.
Basis
- GB 50500-2013 Code of bills of quantities and valuation for construction works, reinforcement works
- GB 50010-2010 (2015 edition) Code for design of concrete structures, detailing provisions
- GB 50666-2011 Code for construction of concrete structures, reinforcement works
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.
Cite this page
Use this format in reports, method statements or coursework. The link is permanent.
Building Calculator. Rebar Cost Calculator. 2026-10-25. https://jianzhujisuan.com/en/rebar-cost
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.