Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.

Roof trusses


Published on

About trusses

Published in: Engineering
  • Sex in your area is here: ❶❶❶ ❶❶❶
    Are you sure you want to  Yes  No
    Your message goes here
  • Follow the link, new dating source: ❶❶❶ ❶❶❶
    Are you sure you want to  Yes  No
    Your message goes here

Roof trusses

  1. 1. PowerPoint® Presentation Unit 50 Roof Trusses Truss Types and Components • Principles of Truss Design • Truss Fabrication • Installing Roof Trusses • Truss Safety
  2. 2. Unit 50 — Roof Trusses Roof trusses are commonly used in residential construction. Metal plate connectors fasten the truss components together.
  3. 3. Unit 50 — Roof Trusses Roof trusses serve the same purpose as rafters but provide a larger unsupported span.
  4. 4. Unit 50 — Roof Trusses Various roof truss designs can be combined to form intersecting roofs.
  5. 5. Unit 50 — Roof Trusses A variety of standard roof truss designs are available. An endless number of variations of the standard designs are possible.
  6. 6. Unit 50 — Roof Trusses Galvanized metal connector plates tie together chords and web members and distribute and transfer loads between adjacent members. The teeth are very sharp and should be handled carefully.
  7. 7. Unit 50 — Roof Trusses Hinge plates may be used as an alternative to piggyback trusses. The top chords are aligned at the peak and nails are driven through the prepunched holes.
  8. 8. Unit 50 — Roof Trusses The balance of tension and compression gives a truss its ability to carry heavy loads and cover wide spans.
  9. 9. Unit 50 — Roof Trusses A tight fit between truss members is essential to the structural integrity of the truss.
  10. 10. Unit 50 — Roof Trusses During manufactured truss assembly, metal plate connectors are pressed into truss components.
  11. 11. Unit 50 — Roof Trusses When framing intersecting roofs, valley trusses are installed over the roof sheathing. Hip roofs can be framed using a Dutch hip system where truss jack rafters are attached to a hip truss.
  12. 12. Unit 50 — Roof Trusses Light trusses can be positioned by hand after they are placed upside down between the exterior walls of a building.
  13. 13. Unit 50 — Roof Trusses Longer and heavier trusses should always be hoisted by crane in an upright position.
  14. 14. Unit 50 — Roof Trusses Metal spacers such as these are used to properly space trusses and are not designed to be used as bracing. Sheathing is applied directly over the spacers.
  15. 15. Unit 50 — Roof Trusses Truss anchors and hangers are used to attach trusses to other structural members.
  16. 16. Unit 50 — Roof Trusses For one-story buildings, the first truss is placed along the double top plate and is secured with vertical, horizontal, and lateral ground braces. For multistory buildings, ground braces are attached to the subfloor.
  17. 17. Unit 50 — Roof Trusses Temporary diagonal braces should be installed across the top chords of the trusses at least every 30′ starting from one end of the building. Temporary lateral braces are installed at 8′-0″ intervals.
  18. 18. Unit 50 — Roof Trusses Permanent metal braces may be installed between roof trusses as lateral bracing.
  19. 19. Unit 50 — Roof Trusses Roof anchors are installed to provide an anchorage point for lifelines of personal fall-arrest systems.