Calculates the maximum allowable span for a wood beam based on load, beam dimensions, and wood species.
Start with your values, or try a preset.
Enter Load on Beam (lbs), Beam Width (inches), Beam Depth (inches), Wood Species, and Allowable Bending Stress (psi) in the units shown.
Read Maximum Allowable Span (feet), Maximum Bending Moment (lb-in), Section Modulus (inĀ³), Required Section Modulus (inĀ³), and Beam Sufficiency in the results panel. Results update as you change the inputs.
Choose a preset to load an example, then adjust the values for your situation.
See the inputs and their calculated results.
Load on Beam (lbs): 1,500; Beam Width (inches): 8; Beam Depth (inches): 10; Wood Species: Southern Pine; Allowable Bending Stress (psi): 1,500
Maximum Allowable Span (feet): 72.73929675 feet; Maximum Bending Moment (lb-in): 2,250 lb-in; Section Modulus (inĀ³): 133.3333333 inĀ³; Required Section Modulus (inĀ³): 1.5 inĀ³; Beam Sufficiency: Sufficient
Load on Beam (lbs): 2,000; Beam Width (inches): 6; Beam Depth (inches): 12; Wood Species: Douglas Fir-Larch; Allowable Bending Stress (psi): 1,600
Maximum Allowable Span (feet): 77.45966692 feet; Maximum Bending Moment (lb-in): 3,000 lb-in; Section Modulus (inĀ³): 144 inĀ³; Required Section Modulus (inĀ³): 1.875 inĀ³; Beam Sufficiency: Sufficient
Load on Beam (lbs): 500; Beam Width (inches): 4; Beam Depth (inches): 8; Wood Species: Spruce-Pine-Fir; Allowable Bending Stress (psi): 1,200
Maximum Allowable Span (feet): 59.34385496 feet; Maximum Bending Moment (lb-in): 750 lb-in; Section Modulus (inĀ³): 42.66666667 inĀ³; Required Section Modulus (inĀ³): 0.625 inĀ³; Beam Sufficiency: Sufficient
Continue with another tool on a related topic.
Estimates how many items or boxes fit on a standard pallet or how many pallets are needed for a shipment.
Calculates the number of light bulbs needed to adequately illuminate a room based on its dimensions, desired light level, and bulb specifications.
Converts a decimal inch measurement into its equivalent fractional representation (inches and fractions of an inch).
Calculates the taper length and angle based on the large diameter, small diameter, and taper length.