Floor Joist And Cross Beam Design

Superimposed dead load including mechanical and electric load w sd 8 psf.

Floor joist and cross beam design.

Continuing on from part 3. Beam design example. Cross sectional area nominal adjusted wood education institute reference value. W d 10 psf.

W l 40 psf. In this video we discuss design and analysis procedures for joists beams and girders. For structural engineering services in massachusetts and new hampshire. Both the 2009 irc and the dca6 09 allow 2 southern pine 2x10s to span 13 feet 1 inch at 24 inches on center at a design load of 50 psf.

What is a beam. Wood member design asd or lrfd compares demand to capacity. Floor beam span tables of residential structural design we will now look at roof rafter and beam design. Top of beam supported by floor joists at 16 in o c.

Joists are the repeated structural members that are used to build a deck frame. The minimum size joist to be used in deck construction depends on the number of footings and beams that will be installed. This sample table gives minimum floor joist sizes for joists spaced at 16 inches and 24 inches on center o c for 2 grade lumber with 10 pounds per square foot of dead load and 40 pounds of live load which is typical of normal residential construction. The image below shows a cross section of our simple 12 x 13 house from the joist span tables section of this tutorial.

So we now have adequately sized floor joists and an adequately sized floor joist beam for our 24 x 13 house. True floor joist span calculations can only be made by a structural engineer or contractor. S 8 ft. A beam is the main load bearing element for the structural soundness of your deck s roof.

Floor joists or beams provide the below surface support for the wood subfloor of a room. Beam design example check notched 3 2x12 beam for shear. L 16 ft. That means these joists can span the 12 foot depth of the deck and the beam can be located at the perimeter.

Design of 3 3x12 beam with southern pine. Pier and beam foundations offer a high level of versatility specific not only to the dead live seismic and wind loads to be supported and or restrained but also to the girders or sill beams and floor joists and their respective span capabilities. Joists 2x12 floor beam notched to 9 1 4 at bearing 3 2x12 floor beam post in wall under beam end bearing wall studs. Let s consider a basic gable wood roof framing design.

In the table above the widest floor beam span for 12 of supported floor joists is 14 7 if using a 5 ply 2 x 12. Our floor joist beam can span a maximum of 13.