Learning how to build roof trusses requires patience and attention to detail. A typical residential roof will need a truss called a Fink truss that brings added stability. This truss style has four internal joists that make the shape of a “W” aligned with the centerline of the truss’s triangle. Building a roof truss correctly is incredibly important so please do not attempt it if you are not confident in your ability.
Directions for How to Build Roof Trusses
- Consult local building codes to learn the minimum height necessary for the roof on your building.
- Measure the width of the building that the truss will span.
- Determine the height of the roof that you intend to build.
- Apply these dimensions to figure out the length of the 3 chords that form the truss triangle.
- The bottom chord will be the width of the building plus 0.25 inches.
- The two top chords must connect in the middle to form the peak of the roof gable.
- Calculate the lengths needed for the 4 internal joists that form the “W” bracing the truss internally.
- Draw a detailed sketch of the truss design on graph paper or use architectural software to create the diagram.
- Find out if you may use homemade plywood gusset plates or if building codes require factory-made steel gusset plates.
- If you can use plywood gusset plates, cut the pieces with a circular saw.
- Take your building plan to local authorities for approval.
- Upon approval, arrange your lumber on a flat surface.
- With the assistance of a triangle square, mark cut lines on the lumber and double check measurements as you go.
- Clamp your first board to a table or across sawhorses.
- Perform all cuts with a jigsaw and proceed through all pieces of lumber.
- Fit the chords and internal joists together on the ground to form your first truss.
- Spread construction adhesive with a putty knife on the joints and glue all pieces together.
- After glue sets, brace all joints by attaching the gusset plates.
- Glue plywood gussets first and then drive screws into the wood.
- Glue steel gussets and drive screws through the holes already in the metal.
- Let truss cure overnight.