Roof Truss Step Bottom Chord

It has been cut adjacent to a node point.

Roof truss step bottom chord.

To reinforce the ends of the trusses 3 4 inch plywood gussets were to be attached to both sides of each truss with 10d nails 3 inches on center on all chords. The bottom chord is also called a scissors truss. For example if a truss has a span of 26 then the bottom chord can be built with two boards 16 and 10 which allows for no scrap and waste and is the most efficient for price savings. Most economical when the difference in slope between the top and bottom chords is at least 3 12 or the bottom chord pitch is no more than half the top chord pitch.

The bottom chord establishes the lower edge of a truss. The bottom chord therefore carries combined stress of both tension and bending of the truss. The span in short is the length of the bottom of the truss. The adjoining trusses appear slightly out of plain.

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. It will attach to the bottom of each end of the rafters with a straight length of wood. Some spans have a lower rate per foot than others. This is where you will make a bottom chord.

One truss cut only at the third point. Create a bottom chord while you have established the angle of the trusses with your rafter pieces and cut them in the necessary lengths they still need more support to finish the structure. To keep the plywood from cupping under the load 2x4 squash blocks were to be inserted between the top and bottom chords.