In this post we will learn how to correctly size a roof rafter based on its span, spacing and species of wood used. Fun Tip: To learn the difference between the International Residential Code …

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 …

Mar 21, 2025 · Rafter spacing is the horizontal distance between the parallel rafters measured from one rafter’s center to the next one. It helps determine the number of rafters based on the …

What size Rafter do you need for 10′, 12′, 15′, 16′, 18′, 20′ & 24 foot span, depends on many factors like the type of wood species (S. Pine, Doug. Fir, Hem-fir, SPF and etc), the load they …

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 …

Oct 17, 2023 · The International Residential Code (IRC) 2021 specifies roof rafter spacings of 12″, 16″, 19.2″, and 24″.The common sizes for rafters include 2×4, 2×6, 2×8, 2×10, and 2×12. For …

Jun 27, 2024 · Rafter spacing can sit at 12, 16, 19.2, or 24 inches apart, depending on board size, wood species, expected loads, and rafter length. A key part of understanding proper roof rafter …

Feb 23, 2010 · Whether you're building a shed roof or adding a dormer to your second story, it is important to choose the proper size rafter. This Sizing Guide for Roof Rafters will help …

Designing appropriate rafters for a building requires assessing several key factors: The rafter size must be adequate to support expected dead, live, wind, and snow loads, calculated based on …

Spacing: common rafter spacing is 16 or 24 inches on center (OC), but it can vary based on local building codes and the type of roof material. Span : the span of roof rafters is determined by …