Roof Truss Chord

The chord size and web configuration are determined by span load and spacing.

Roof truss chord.

Closed in which the bottom chord is horizontal and at the foot of the truss and open in which the bottom chords are raised to provide more open space also known as raised bottom chord trusses. In span and 1 2 in. The parallel chord or flat truss gets its name from having parallel top and bottom chords. All truss designs are optimized to provide the most economical configuration for the specific application.

Flat the most economical flat truss for a roof is provided when the depth of the truss in inches is approximately equal to 7 of the span in inches. Closed open distinction is used in two ways to describe truss roofs. Complying with the erection tolerances specified in sbca s bcsi b1 summary sheet is critical to achieving an acceptable roof line. These steel joints are needed to support the overall truss.

It is most often used for roof construction. The bottom chord which is the bottom of the framed truss. These trusses are positioned on the top plate of the endwall so the entire bottom chord is supported by the wall. Finally there are the gussets that hold the framed truss together.

Box 177 la crescent mn 55947 507 895 8400. Variance from the design dimensions is also allowed. The same thing is true for the bridge of the truss. And in height by as much as 1 4 in.

Hip end trusses that are supported by hip truss and creates hip plane. Truss that creates roof planes and does not support other trusses truss that creates hip plane by truncating and allowing hip jacks truss top chords to fly over. Any weight imposed on the end truss is directly transferred to the endwall which transfers the weight to the foundation. See gusset construction below.

There are three parts to the roof truss that you have to know. End trusses close in the end of a building and provide a nailing surface for the upper end wall or rigid sheathing. Bottom chords is at least 3 12 or the bottom chord pitch is no more than half the top chord pitch. Dropped chord roof truss.

The more complex the truss framework is the greater quantity of these joints will be required. For example table 3 5 1 allows identical trusses to vary in span by as much as 1 2 in. Similar to the raised heel truss this type also creates a vapor barrier creating great insulation characteristics. Truss that supports creeper trusses and creates hip roof plane.

Finally the truss calculator will compute the best dimensional method to connect the pieces of the truss with steel joints and a bridge. There are two main types of timber roof trusses. Hip end trusses that are supported by. Then there is the top chord or rafters that are angled to make the roof pitch.