Steel Shed Purlin
Find the required section modulus and moment of inertia of roof purlins for a steel shed, or check a purlin from the catalogue.
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About this calculator
Enter the span, spacing, slope and loads. The calculator applies gravity and wind-uplift combinations and tells you the purlin size needed.
How it's calculated
- wu = 1.2D + 1.6Lr; uplift = W − 0.9D
- Mu = wL²/8; Sx,req = Mu/(0.9Fy)
- Ix,req from δ = 5wL⁴/384EI ≤ L/180
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). Steel Shed Purlin [online calculator]. https://katariaengineering.com/tools/steel-shed-purlin-calculator.html
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