40 Construction Lumber Span Tables Update

View joist rafter tables.

Construction lumber span tables. The species of lumber size of lumber and the load it carries. Span tables allow users to choose an appropriate size and stress grade to achieve spanning needs. Joist span table use these tables to determine floor joist spans based on grade of lumber size of joist floor joist spacing and a live load of 30 lbs ft 2 or 40 lbs ft 2 these tables can also be used to determine deck joist span. Simplified maximum span tables for selected visual and mechanical grades of southern pine lumber in sizes 2 4 thru 2 12.

Step 2 span table. Listed are 46 tables based on common loading conditions for floor joists ceiling joists and rafters. Beam span maximums are based on a maximum anticipated live load. You can also use the wood beam calculator from the american wood council website to determine maximum rafter and joist lengths.

This span table excerpt shows two possible sizes. Select the appropriate table in span tables for joists and rafters. For simple construction such as domestic construction this can be determined from span table supplements in as1684 2 and as1684 3. Using table f 2 figure 3 check each lumber size to see if a 16 inch spacing will permit a span of 15 feet 1 inch.

There are several beam span tables for all the species of wood. Fewer posts on upper level decks are typically more desirable to the occupants and this drives the use of larger framing materials for longer spans. The 2015 span tables for joists and rafters updates the 2012 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 2015 international building code and 2015 international residential code. The table of contents indicates that table f 2 watches these loading conditions.

Building codes for residential decks only require 40 psf. Stress grades and timber sizes combine to determine the spanning ability of load carrying members. Tables w 1 and w 2 of design values for joists and rafters a supplement to these span tables provide such values for them ostc ommonly used framing sizes. Sample floor beam span table.

A tutorial for using the span tables is also available. Use of these span tables requires reference to the applicable design values for the various species and grades of lumber. The table below shows an excerpt from a maximum span for built up douglas fir floor beams table for supporting not more than one floor. This table is simply a sample and may not be valid for your region.

Modulus of elasticity e bending design values f b.