Floor Joist And Cross Beam Design

Joists are the repeated structural members that are used to build a deck frame.

Floor joist and cross beam design.

The minimum size joist to be used in deck construction depends on the number of footings and beams that will be installed. For structural engineering services in massachusetts and new hampshire. Our floor joist beam can span a maximum of 13. W d 10 psf.

So we now have adequately sized floor joists and an adequately sized floor joist beam for our 24 x 13 house. Nine joists will be needed for the 16 foot width. Floor beam span tables of residential structural design we will now look at roof rafter and beam design. Beam design example check notched 3 2x12 beam for shear.

Floor joists or beams provide the below surface support for the wood subfloor of a room. The image below shows a cross section of our simple 12 x 13 house from the joist span tables section of this tutorial. In this video we discuss design and analysis procedures for joists beams and girders. True floor joist span calculations can only be made by a structural engineer or contractor.

S 8 ft. Beam design example. 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. L 16 ft.

Top of beam supported by floor joists at 16 in o c. W l 40 psf. 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. Though joists may be any size that you desire using typical floor joist and beam specifications ensures that you can find hardware to fit the joists and that the floor provides adequate support for furniture and other items in a room.

Superimposed dead load including mechanical and electric load w sd 8 psf. Continuing on from part 3. Joists 2x12 floor beam notched to 9 1 4 at bearing 3 2x12 floor beam post in wall under beam end bearing wall studs. A beam is the main load bearing element for the structural soundness of your deck s roof.

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. Cross sectional area nominal adjusted wood education institute reference value. That means these joists can span the 12 foot depth of the deck and the beam can be located at the perimeter. 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.

Here we have a wood framed gable roof. Let s consider a basic gable wood roof framing design.