2021 Span Tables for Joists and Rafters

The 2021 Span Tables for Joists and Rafters updates the 2015 edition and provides a simplified system for determining allowable joist and rafter spans for typical loads encountered in one- and two-family dwellings and is referenced in the 2021 International Building Code and 2021 International Residential Code.

A tutorial for using the span tables is also available.

2021 Design Values for Joists and Rafters

A companion Supplement to Span Tables for Joists and RaftersDesign Values for Joists and Rafters tabulates allowable bending (Fb) and modulus of elasticity (E) design values for visually graded and mechanically graded dimension lumber.

This edition has been updated to the 2018 NDS Design Values Supplement. Changes include new design values for Southern Pine and Mixed Southern Pine design values.

Addendum to the 2021 and previous versions to add design values for Non-North American Visually Graded Dimension Lumber per 2018 NDS Supplement Table 4F and Multi-Species and Country Grademarked Visually Graded Dimension Lumber per Table 4G recently added to the 2018 NDS Supplement.