Roof Joist Design Example

The table references have changed in the 2018 version of the irc.

Roof joist design example.

Ij 13 multiple ply bci ajs member. Example joist design for uplift tension webs must be checked for compression c. Continuing on from part 3. In this post we will cover wood roof framing members specifically ceiling joists.

You can earn a ceu by watching the industry version of this webinar then successfully completing the related ceu exam. Timber beam design seismic forces wind forces floor shearwall diagram lateral loads roof diaphragm design shearwall design continuous footing design. Ij 9 bci header table. Floor beam span tables of residential structural design we will now look at roof rafter and beam design.

The design and construction of ceiling joists are found in section r802 4 of the irc. Ij 8 glue nail floor composite action. 2x joists rafters 2 or better 2. Design criteria and specifications a.

Ij 12 design live loads for residential floors. Design examples for strengthening joists example 3 1 strengthening a k series joist with crimped angle webs example 3 2 strengthening a k series joist with rod webs example 3 3 strengthening an end diagonal w2 using double angles example 3 4 strengthening of joist girder chords example 3 5 strengthening of a lh series joist with double angle webs. Since the weight of a roof is fairly static it is easy to design for but engineers do need to think about issues like the accumulation of snow in cold climates layers of roofing materials added over the lifetime of the structure and changes in roofing materials when they determine. Design of steel joist roofs to resist uplift quiz.

Draw the purlin and show the dead loading. Ij 6 2x ceiling joist connection. The allowable ceiling joist span tables in the 2018 version are found in section r802 5. Ij 10 rafter cut length table.

Example joist design for uplift bottom chord lyybraced by bridging y axis lyy better partners. Access to the exam is available for purchase. Ce 331 spring 2002 joist and frame design example 1 2 1. Let s consider a basic gable wood roof framing design.

4x 6x 8x beams headers 1 orbetter. The even distribution of weight across a roof joist network is intended to prevent the roof from collapsing. Example joist design for uplift bottom chord properties llllxx lllzz 24 better partners. Ij 14 minor flange cuts.

2003 international building code. For example a 24cj 1400 800 240 composite joist has a steel joist depth of 24 inches 610 mm a total factored composite load carrying capacity of 1 400 plf 20 4 kn m a factored composite live load capacity of 800 plf 11 7 kn m and a factored composite dead load capacity of 240 plf 3 5 kn m. The image below shows a cross section of our simple 12 x 13 house from the joist span tables section of this tutorial. Ij 16 bci web stiffener.

Draw the shape of the moment diagram below. Calculate the moment due to dead load. Here we have a wood framed gable roof.