Course: Ag Structures
Unit: Structures
Lesson: Types of Trusses
Time Needed: ??
Lesson: Types of Trusses
South Dakota AFNR Standards:
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Ag S 3.1 Write a complete materials list and project cost estimate.
Ag S 4.1 Assemble components of a structure.
Student Learning Objectives:
1. Identify and describe basic types of trusses.
2. Identify parts of a truss.
3. Differentiate between a rafter and a truss.
List of Resources/References:
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DeKorne, Clayton and Wagner, John D. Ultimate Guide to Barns, Sheds, and Outbuildings.
Upper Saddle River, NJ: Creative Homeowner, 2005.
Smith, Howard Bud and Wagner, Willis H. Modern Carpentry. Tinley Park, IL: The GoodheartWillcox Company, 1996.
List of Equipment, Tools, Supplies, and Facilities:
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overhead projector
PowerPoint presentation
popsicle sticks
glue
scissors
truss handout
Course: Ag Structures
Unit: Structures
Lesson: Types of Trusses
Terms:
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truss: a set of rafters with a lower chord that can be used as a ceiling joist and bracing that
increases the strength
rafter: sloped framing part that runs from the roof peak to the top plate of the wall
gusset plates: metal or plywood plates used to hold together the chords and webs of a truss
internal webbing: bracing between the top and bottom chords of a truss to improve the
strength
top chord or upper chord: the two upper sections of a truss
bottom chord or lower chord: the lower section of a truss that can be used as a ceiling joist
Interest Approach: Display the names of common types of trusses on a PowerPoint presentation or on
the board. Howe, fink, fan, king post, queen post, gable end, double W. Ask students if they can
determine what we will be learning about today.
Objective 1: Identify and describe basic types of trusses. (20 – 25 minutes)
1. Split students into groups of 3 or 4.
2. Give students the truss handout.
3. In their groups, students should write a description for each truss. They should also create an
answer key on a separate piece of paper. The descriptions should be written well enough for
another group to identify the type of truss when reading it. When the descriptions are finished,
groups will trade and see if they can accomplish this.
4. While writing the descriptions, students should also construct the seven different types of
trusses. The following supplies should be available for groups to gather: popsicle sticks, glue,
and scissors.
5. Allow 15 minutes for this activity – then have groups trade descriptions. Allow 5 minutes for
groups to identify the trusses described. Discuss how they did.
Objective 2: Identify parts of a truss. (10 minutes)
6. Refer to the truss handout previously given to students.
7. Display the following definitions on a PowerPoint presentation:
a. Metal or plywood plates used to hold together the chords and webs of a truss
b. Bracing between the top and bottom chords of a truss to improve the strength
c. the two upper sections of a truss
d. the lower section of a truss that can be used as a ceiling joist
8. Have students match the descriptions with the picture of the truss parts on the handout.
Course: Ag Structures
Unit: Structures
Lesson: Types of Trusses
9. Display the truss parts illustration on the PowerPoint presentation for students to check their
work.
Objective 3: Differentiate between a rafter and a truss. (5 minutes)
10. Ask students if there is a difference between a rafter and a truss. Have students discuss with a
partner. Take a class vote – write results on the board. Ask students for their thoughts??
11. Display the definitions on the PowerPoint presentation:
a. Rafter: sloped framing part that runs from the roof peak to the top plate of the wall
b. Truss: a set of rafters with a lower chord that can be used as a ceiling joist and internal
bracing that increases the strength
Review: Go through pictures of the basic trusses on the PowerPoint presentation. Have students
answer orally or write down on a piece of paper. Next go through the parts of the truss review
questions – again, have students answer orally or write down on a piece of paper. (5 – 10 minutes)
Application: (Homework) Have students create their own truss (must be original!). They can do this
individually or in groups. Trusses can be drawn on paper or built with popsicle sticks. Students should
be prepared to share with the class tomorrow.
Evaluation: Students will take the quiz on truss names and parts.