Span Tables for Joists and Rafters - 2024 Edition - American Softwood Lumber Standard (PS 20-20) Sizes - Updates and Errata

Oct 12, 2026

Upload by Fahsai

Span Tables for Joists and Rafters (2024 Edition) provides size and loading span reference data aligned with the American Softwood Lumber Standard (PS 20-20). It includes updates and errata and clarifies accuracy precautions, technical inquiries, and liability statements for users. The table listings organize structural guidance by member type—floor joists, ceiling joists, and rafters—then further segment results by deflection limits (L/360, L/240, L/180) and varying live load and dead load combinations.

LanguageEnglish

CategoryGeneral

FormatPDF

Pages52

Reading Time18 min

AccessFree to download

Table of Contents

Explanation of Tables

Floor Joists with L/360 Deflection Limits

Ceiling Joists with L/240 Deflection Limits

Rafters with L/240 Deflection Limits

Rafters with L/180 Deflection Limits

SPAn tAbLeS FOR JOIStS AnD RAFteRS 2024 eDItIOn American Softwood Lumber Standard (PS 20-20) Sizes Updates and Errata While every precaution has been taken to ensure the accuracy of this document, errors may have occurred during development. Updates or Errata are posted to the American Wood Council website [at www.awc.org](at www.awc.org). Technical inquiries may be addressed to [info@awc.org](info@awc.org). The American Wood Council (AWC) is the voice of North American traditional and engineered wood products. From a renewable resource that absorbs and sequesters carbon, the wood products industry makes products that are essential to everyday life. AWC’s engineers, technologists, scientists, and building code experts develop state-of-the-art engineering data, technology, and standards on structural wood products for use by design professionals, building officials, and wood products manufacturers to assure the safe and efficient design and use of wood structural components. SPAn tAbLeS FOR JOIStS AnD RAFteRS 2024 eDItIOn American Softwood Lumber Standard (PS 20-20) Sizes While every effort has been made to insure the accuracy of the information presented, and special effort has been made to assure that the information reflects the state-ofthe-art, neither the American Wood Council nor its members assume any responsibility for any particular design prepared from this publication. Those using this document assume all liability from its use. Copyright © 2023 American Wood Council [info@awc.org](info@awc.org) [www.awc.org](www.awc.org) tAbLe OF COntentS Table No. Description of Tables Page Explanation of Tables ...................................................................................................................................... 1 FLOOR JOISTS WITH L/360 DEFLECTION LIMITS F-1 Live Load of 30 psf plus dead load of 10 psf.......................................................................................................... 4 F-2 Live Load of 40 psf plus dead load of 10 psf.......................................................................................................... 5 F-3 Live Load of 50 psf plus dead load of 10 psf ......................................................................................................... 6 F-4 Live Load of 60 psf plus dead load of 10 psf ......................................................................................................... 7 F-5 Live Load of 40 psf plus dead load of 20 psf ......................................................................................................... 8 F-6 Live Load of 50 psf plus dead load of 20 psf ......................................................................................................... 9 F-7 Live Load of 60 psf plus dead load of 20 psf ....................................................................................................... 10 CEILING JOISTS WITH L/240 DEFLECTION LIMITS C-1 Live Load of 10 psf plus dead load of 5 psf ......................................................................................................... 11 C-2 Live Load of 20 psf plus dead load of 10 psf ....................................................................................................... 12 RAFTERS WITH L/240 DEFLECTION LIMITS R-1 Live Load of 20 psf plus dead load of 10 psf ....................................................................................................... 13 R-2 Live Load of 30 psf plus dead load of 10 psf ....................................................................................................... 14 R-3 Live Load of 40 psf plus dead load of 10 psf ....................................................................................................... 15 R-4 Live Load of 50 psf plus dead load of 10 psf ....................................................................................................... 16

FAQs

What document standard and edition does this span table reference?

It is the 2024 Edition associated with the American Softwood Lumber Standard (PS 20-20).

How are the span results organized in the document?

The contents are organized by structural member type (floor joists, ceiling joists, rafters) and by deflection limit tiers such as L/360, L/240, and L/180, with live-load and dead-load combinations listed in tables.

Where are updates or errata provided?

Updates or errata are posted to the American Wood Council website at www.awc.org.

Oct 12, 2026

Upload by Fahsai