Residential Header & Beam Sizing Calculator

Calculation Mode

Opening & Member

Span (ft)

Span (in)

Lumber Type

Species Group

Grade

Number of Plies

Member Depth

IRC Load Condition

Supported Loads

Building Width (ft)

Used to determine tributary width (building width ÷ 2 + eave)

Eave/Overhang (ft)

Roof overhang beyond exterior wall. Adds to tributary width for roof loads.

Ground Snow Load (psf)

Enter 0 if roof live load governs (most areas below ~30 psf ground snow)

Floor Live Load (psf)

Applied Loads (NDS)

Tributary Width (ft)

Dead Load (psf)

Floor Live (psf)

Roof Live (psf)

Snow Load (psf)

Additional Uniform Load (plf)

Additional dead load applied directly as plf (e.g., wall above, point loads distributed)

Load Duration Factor (C_D) Override

Deflection Limit — Live Load

Deflection Limit — Total Load

Analysis Options

Reduce shear at d from support face (NDS 3.4.3.1)

Applies to uniformly loaded beams with full bearing. Conservative if unchecked.

Important: This calculator provides engineering analysis per NDS 2018 and IRC 2021. All results must be verified by a licensed Professional Engineer before use in construction. Local code amendments and site-specific conditions may require additional analysis.