Floor & Ceiling Joist Span Estimator

Quick-check a wood joist or TJI against span tables.

Joist (e.g. 2x10)Spacing (in o.c.)Species factor (1.0–1.6)

Result

Allowable span

0.1 ft

About this tool

Pick species, grade, joist size, and spacing to get an allowable span and a ruling L/360 deflection check for a given uniform load. Targets r/Construction and r/Carpentry 'how far can a 2x10 span' threads.

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