Rafter Span Tables - Use these tables to determine lengths, sizes, and spacing of rafters based on several factors such as species, load, grade, and spacing. Visit the roof framing page for more information on cutting roof rafters, and visit the roof pitch calculator for determining rafter lengths based on rise and run.

These span tables for joists and rafters are calculated on the basis of a series of modulus of elasticity (E) and bending design values (F b). Additionally, compression perpendicular to grain design values (F c⊥) are included as a consideration for selection of joists and rafters.

Joists and rafter spans for common loading conditions can be determined. A “span options” calculator allows selection of multiple species and grades for comparison purposes.

Section R802.4 outlines the wood roof rafter framing criteria which also includes prescriptive span tables. In this post we will learn how to correctly size a roof rafter based on its span, spacing and species of wood used.

Rafter Span Tables - Use these tables to determine the maximum span of a rafter, given the size, spacing, species, and grade of lumber.

Resources provide a simplified system to determine allowable joist and rafter spans in one- and two-family dwellings, and the companion supplements for tabulating allowable bending and modulus of elasticity design values for visually graded …

ALLOWABLE SPANS IN FEET AND INCHES #2 Spruce-Pine-Fir ... Only with ceiling joists located near the base of the rafter at the bearing wall (1/7.5 or less) RAFTER SPAN TABLES

In this guide, we’ll explain rafter spacing, code requirements, roof rafter span tables, and rafter spacing calculators. We’ll discuss 16” and 24” spacing, how to calculate the number of rafters required, 19.2” spacing, and the spacing when using metal roofing and for …

Jan 18, 2019 · These rafter span tables provide the best reference to quickly and easily determine the maximum span for all grades of southern pine according to the 2018 International Residential Code.

This calculator helps users quickly determine if a given rafter length and spacing are suitable for their load requirements, ensuring a strong and stable roofing structure.