Column Size Calculator
Preliminary RCC column size from tributary area, number of floors and loads, with steel area and bar suggestion (ACI 318 tied column).
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About this calculator
Estimate a starting column size from the area it supports and the number of floors above, using factored loads and the ACI tied-column capacity formula.
How it's calculated
- Pu = 1.2D + 1.6L over the tributary area and all floors
- φPn = 0.65 × 0.80 × [0.85 f′c (Ag − Ast) + fy Ast]
- Ag = Pu ÷ (0.52 × [0.85 f′c (1 − ρ) + fy ρ])
What is the minimum column size for a house?
9″ × 12″ is common in small houses, but 12″ × 12″ or larger is recommended for buildings in seismic zones like AJK.
Results are calculated from the values you enter using standard formulas. Download the PDF to keep a record. For certified testing, design or construction, talk to our engineers.
Kataria Engineering & Consultancy Services (2026). Column Size Calculator [online calculator]. https://katariaengineering.com/tools/column-size-calculator.html
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