Roof Joist Design Example

Ij 8 glue nail floor composite action.

Roof joist design example.

The table references have changed in the 2018 version of the irc. The allowable ceiling joist span tables in the 2018 version are found in section r802 5. Ij 12 design live loads for residential floors. Here we have a wood framed gable roof.

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. Continuing on from part 3. Example joist design for uplift bottom chord properties llllxx lllzz 24 better partners. The design and construction of ceiling joists are found in section r802 4 of the irc.

Let s consider a basic gable wood roof framing design. You can earn a ceu by watching the industry version of this webinar then successfully completing the related ceu exam. Design a typical floor joist for the two story office building indicated below. Example joist design for uplift tension webs must be checked for compression c.

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. Ij 10 rafter cut length table. Ij 16 bci web stiffener.

Design criteria and specifications a. Example joist design for uplift bottom chord lyybraced by bridging y axis lyy better partners. Floor beam span tables of residential structural design we will now look at roof rafter and beam design. 4x 6x 8x beams headers 1 orbetter.

Ij 14 minor flange cuts. Ij 13 multiple ply bci ajs member. 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 even distribution of weight across a roof joist network is intended to prevent the roof from collapsing.

Access to the exam is available for purchase. In this post we will cover wood roof framing members specifically ceiling joists. Ij 6 2x ceiling joist connection. 2x joists rafters 2 or better 2.

Ij 9 bci header table. Calculate the dead load on a typical purlin. Timber beam design seismic forces wind forces floor shearwall diagram lateral loads roof diaphragm design shearwall design continuous footing design. 2003 international building code.

Ij 5 joist to hip beam connection. Draw the purlin and show the dead loading. Calculate the moment due to dead load.