Concrete Column Calculator — m, m³, rebar
How to use this calculator
Select column shape (square, rectangular, or circular), enter dimensions and choose unit (m, cm, or mm) from the dropdown. Set height and number of columns. Results update instantly with volume, weight, and bag count.
Cost — pick ready-mix per m³, 50 kg bags, or 25 kg bags. Select currency.
Reinforcement — vertical bars 12–25 mm with ties 8–10 mm, lap splices per EC2 §8.7, min/max steel ratios (0.2%–4% Ac per §9.5.2).
Labor — rate per column, per m³, or flat price.
Saved Calculations
| Time | Shape | Size | Qty | Vol m³ | Cost | Rebar | Rebar | Labor | Total |
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How to Calculate Concrete for Columns (Metric)
This calculator estimates concrete volume in cubic meters, bags (25 kg and 50 kg), reinforcement (vertical bars and ties per EN 1992-1-1), and cost for square, rectangular, or circular columns. Enter dimensions in mm, cm, or m using the dropdown selector. Set column height (standard: 2.4–3.6 m) and number of columns.
Reinforcement per EN 1992-1-1 (Eurocode 2)
Column longitudinal steel must be between 0.2% and 4% of gross cross-section area (Ac) per EC2 §9.5.2. Minimum 4 bars for rectangular columns. Tie spacing must not exceed: 20 times the smallest longitudinal bar diameter, the lesser column dimension, or 400 mm (§9.5.3). Lap splices are calculated at 40db per §8.7.
Formulas
Square: V = side² × height. Rectangular: V = width × depth × height. Circular: V = π/4 × diameter² × height. Concrete density: 2,400 kg/m³. Tie perimeter = 2×(width + depth) − 8×cover + 2×hook length.
FAQ
What is the minimum column size? EC2 recommends minimum 200 mm for non-seismic and 250 mm for seismic zones. How many bags per column? A 300×300×3 m column needs about 0.27 m³ or 12 bags of 50 kg concrete.
