Joist Span Calculator | Free Construction Calculators

Calculate maximum allowable span for floor joists based on size, spacing, and load requirements.

About Joist Spans

This calculator determines the maximum span for floor joists based on lumber properties, spacing, and applied loads. Results consider both bending strength and deflection limits per building code requirements.

Important Note

Always verify calculations with local building codes and span tables. Professional engineering review is recommended for critical applications or non-standard conditions.