Joist parameters

Enter your lumber species, size, and spacing

IRC R507.5

Lumber species / grade

Joist size

Joist spacing (o.c.)

Your actual joist span (ft) — distance between supports

Deck live load — typically 40 psf residential

Joist cross-section

Span check results

IRC 2021 Table R507.5

Maximum allowable span

—

Your span

—

Margin

—

Utilization

—

Span options for your species

🪵 Shop pressure-treated deck lumber:

Home Depot Lowe's Joist hangers

Deck Joist Span Calculator