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Structural Calculator

PRO

Calculate beam sizes, joist spacing, and footing dimensions. Select wood species, enter span and load values for NDS-based structural sizing.

Input Parameters

Typical: Floor 40-80 PLF, Roof 25-50 PLF, Deck 50-100 PLF

Recommended Beam

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Max Moment (ft-lbs)

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Load Diagram

150 PLF 12 ft span 2x 2x10 R1 R2

Calculation Details

Total Load--
Max Shear--
Fb Allowable--
Req'd Sx/Ply--
Defl Limit (L/360)--
Actual Deflection--

Load Path Explanation

Loads travel from the roof/floor surface through the sheathing to the joists, then to beams, then to posts/columns, then to the foundation footings, and finally into the soil. Each element must be sized to handle its tributary load. This calculator sizes the beam based on the total PLF (pounds per linear foot) applied along the span. The beam must resist both bending (moment) and deflection within code limits (L/360 for live load, L/240 for total load).

Disclaimer: This tool provides preliminary sizing for reference only. Always verify with a licensed structural engineer before construction. Actual sizing depends on load path, connections, bearing conditions, and local building codes.