How to Design Metal Trusses

Metal trusses are also often used on bridges.

Trusses form the roof of homes. They are most often made out of 2-inch by 4-inch pieces of lumber, but can also be constructed of metal, similar to how steel studs are constructed. Before you begin to construct your trusses and put them together, it is necessary to design them to your desired specifications. Designing how you will put together your metal trusses is no different than designing wood trusses and requires careful measurements and preparation.

Things You'll Need

• Tape measure

Instructions

1. Determine the type of roof you will be installing. The truss design will vary depending on the type of roof you have. Most trusses are installed every 16 inches on center along each side of the roof. They meet in the middle at the top of the roof and are braced at the bottom with a horizontal truss.

2. Measure the length and width of the roof to determine how many trusses will be needed for installation. Run a tape measure from one end to the other and record the measurement for the length. Repeat the same process for the width of the building. This will give the measurement of the metal truss that will run horizontally across the roof.

3. Mark the truss locations every 16 inches on center beginning at one end of the roof and working toward the other. Draw a small pencil mark every 16 inches along the length of each truss. Repeat the process for the other side of the roof. This will mark the center of the truss locations.

4. Decide on how tall you want the roof to be. This will tell you how tall the trusses will need to be. This measurement will vary, depending on how high your want the ceiling of your attic to be.

References

• Fox Metal: Custom Truss Design and Build
• JFBA: Truss Design and Estimating