UNIT 3: ROOF TRUSSES KEY CONCEPTS 1. Identify tools needed for rolling trusses 2. Identify proper nails and sizes 3. Setting roof trusses 4.

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1 KEY CONCEPTS 1. Identify tools needed for rolling trusses 2. Identify proper nails and sizes 3. Setting roof trusses 4. Site Safety and Hazards INSTRUCTIONAL ACTIVITIES 1. Complete Follow Up Worksheet from Unit 2 Framing 2. Identify tools: students discuss use of each tool 3. Identify and discuss different roof designs 4. Discuss hip roof truss components and setting of trusses 5. Discuss hurricane clips 6. Discuss the function of fascia and how it is installed 7. Common roofing hazards and safety issues 8. Summarize Key learning points ASSESS LEARNING OF KEY CONCEPTS Students will need to demonstrate knowledge of hip roof design and truss layout, function of hurricane clips, and function and proper installation of fascia. 1

2 TOOLS USED UNIT 3: E A B C D G K F I H J A. Pry Bar F. Reciprocating saw B. Cats Paw G. Speed Square C. Hammer H. Level D. Circular Saw I. Chalk Line E. Power Miter Saw J. Tape Measure K. Sledge Hammer K. Trus-Lock (not pictured) MATERIALS USED A. Trusses D. Hurricane clips B. 8d nail E. 2x6 fascia C.16d nail F. 16d galvanized nails G. 1½" tico nails 2

3 Truss ID C24 Truss Type Common H24A Cal Hip H24B Cal Hip HM24 Hip Master (or Girder Truss) HR1 Hip Rafter J10 J12 J2 J2A J4 J4A J6 J8 3

4 Wood trusses are pre-engineered and shop made. Trusses are typically constructed of 2x4s and 2x6s. Truss members are connected with metal gang-nail plates Roof elements are applied directly to the top chords. Ceiling (drywall) may be applied directly to the bottom chords. 4

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7 Steps to setting the shed roof trusses is shown here. 7

8 SETTING 1. Our truss design is dependent on deciphering the plans that come from the truss manufacturer. Of importance is the location of the girder truss (hip master) that the jack trusses will be attached to. There is a specific order and place for the trusses so please take the time to understand where everything goes. See diagrams on page One key to reading the plans is knowing the numbering system. On page 4 the numbers on the truss layout means 5 feet, 11 inches, and 4 /16 or ¼ inches. 3. Place the girder truss (or hip master) in its location and attach the center jack truss to keep the girder truss from tipping over. String line the bottom of the girder to keep it and the jack trusses straight. 4. Consult the layout that came from the truss company, but most of the time the layout for the jack trusses starts from the corners and is every 24" to the center of the truss. This is from each corner, so the plywood will have a funny layout when you get to the center. 5. The main trusses are every 24" on center from the girder truss toward the other girder truss. 6. After the trusses are installed, the fascia board that the rain gutter attaches to can be installed. See diagram on page 9. Fascia is attached with galvanized 16d nails. Fascia can be cut on an angle to match the roof slope. 7. Some of the material we will be putting up will be pre-painted. Anything that will have an exposed nail head needs to be galvanized. 8. After the trusses have been installed, the hurricane clips may be installed. Use the 1½" tico nails. Needle nose pliers may be helpful to hold nails in tight places. 8

9 Placement of sub-fascia, fascia, soffits, and insulation baffles is shown here. 9

10 SAFETY GUIDELINES FOR A. This is a hard hat day! B. Use safety equipment such as glasses, earplugs, gloves, etc to minimize the risk of injury. C. Do not wear jewelry at the work site. Jewelry, long hair, and loose fitting clothes can get caught in saws. Sandals and flip flops are not allowed on the work site. D. Use caution when lifting and get help with lifting heavy items. E. Use extreme caution on ladders and scaffolding; work at a height you are comfortable with. F. Immediately remove nails from used boards. G. Do not use unfamiliar power tools until you have received proper instruction. H. Be aware of your surroundings and watch for holes, trip hazards, and other people. 10

11 FOLLOW ALONG WORKSHEET Please use the area below to take notes about the major subject headings listed. NEW TOOLS: TRUSS COMPONENTS: MAJOR STEPS IN SETTING : ADDITIONAL NOTES: 11

12 FOLLOW UP WORKSHEET: UNIT 3: Fill in the Blank: Please fill in the blank of each question with the corresponding answer from the key below. 1. help attach the roof to the frame of the house. 2. Galvanized nails are used anywhere there will be an nail head. 3. A hip roof has surfaces. 4. are spaced 24" apart center to center. 5. attaches to the ends of the trusses and is what the rain gutters are attached to. Hurricane clips Exposed Fascia Roof trusses Four Identify: Please explain the difference between a girder truss and a jack truss. Choose one safety precaution particular to this unit that you can implement either on the job site or in your home. In the area below describe why this precaution is necessary to ensure safety. 12