WWPA is the leading source of technical information on Western lumber spans and offers a variety of design aids to assist professional users. One of the more popular sources of span information is the Association's Western Lumber Span Tables book, which is available here in a digital format.
Individual tables published in Western Lumber Span Tables (572) can be viewed on this page using Adobe Acrobat. Download the entire book at the WWPA Store.Western Lumber Span Tables book (PDF file)
Download full book ($15.00)
To select an individual table, click on a pattern group below.Floor Joists
Roof Rafters L/180
Roof Rafters L/240
Roof Rafters L/360
Spans for Structural Decking (2" and 3" nominal in thicknesses)
The structural decking spans above are published in Western Lumber Products Use Manual (A) and can be viewed on this page using Adobe Acrobat.
Spans for built-up members, see WWPA Tech NoteDesign Load Tables for Solid-Sawn Lumber Beams and Headers in the Tech Notes section.
Span information for U.S. and Canadian Douglas Fir-Larch and Douglas Fir (North) combination are detailed in the Tech Note Design Values for U.S. and Canadian Species Group Combinations,Tech Notes section.
WWPA also offers software design tools that can be used to determine spans for Western lumber products. These tools can be downloaded from the WWA website.
To order these publications or design tools, go to the WWPA Online Literature Store.
While every effort has been made to ensure the accuracy of the Western lumber information included in this Online Technical Guide, WWPA accepts no responsibility for errors or omissions in the information presented herein, or for errors which may occur in downloading and printing any of the files, nor any liability resulting from the use of this information for design and construction applications.
The WWPA Online Technical Guide is copyrighted by Western Wood Products Association in Portland, Oregon. ©