Shear-X Bracket. Roof Ridge Installation Guide for Unblocked Roof Diaphragms

Transcription

1 Shear-X Bracket Roof Ridge Installation Guide for Unblocked Roof Diaphragms

2 Introduction Why Use Shear-X? Shear-X brackets are designed to transfer in-plane shear forces at the ridge line of roof diaphragms The brackets enhance the diaphragm action in Unblocked Diaphragms Roof with Metal Plate Connected Wood Trusses Roof with 2x_ rafters and ridge board/beam

3 Unblocked Diaphragm An Unblocked Diaphragm is one in which the wood structural panels (i.e., plywood or Oriented Strand Board (OSB) roof sheathing) are only required to be attached to the framing members (i.e., rafters or trusses) and the edges of the panels between the framing members are NOT required to be supported by and attached to blocking (e.g., 2x_ lumber) Rafter or Truss Blocking not required between roof framing at structural panel edges

4 Unblocked Diaphragm Most wood framed roof systems in the U.S. are constructed with Unblocked Diaphragms If in doubt, check with the local building code official or a registered design professional to verify the type of roof diaphragm used for your specific project If the roof diaphragm is Unblocked, follow the steps in this installation guide Example of unblocked roof diaphragm Edges of OSB between trusses are unsupported Source:

5 The brackets can be bent to accommodate any roof pitch from flat to 12:12 The design values for the Shear-X brackets have been developed by an ISO/IEC Accredited Product Certification Body based on testing by an ISO/IEC Approved Agency Roof Ridge Installation

6 The roof diaphragm must be sheathed with plywood or OSB wood structural panels installed per the requirements of the building code and the construction documents for the project Rafters and trusses must be minimum 2x4 SPF No. 2 Minimum Requirements

7 Select Shear-X 16 or 24 to match rafter or truss on-center spacing Installation: Step 1

8 Installation: Step 2 Install brackets with 10d (0.131 diameter by 3 long) smooth shank nails. Use of positive placement nail guns greatly increases installation efficiency

9 Installation: Step 3 Consult Shear-X Bracket Roof Ridge Design Guide for Unblocked Roof Diaphragms to determine bracket spacing for your project No. of Shear-X brackets per ridge line - Unblocked roof diaphragm 16" oc No. of Trusses along ridgeline No. of Shear-X 16" brackets per ridge line 1 24" oc No. of Trusses along ridgeline No. of Shear-X 24" brackets per ridge line ) Number of brackets includes a bracket at each end of the ridge line plus brackets spaced evenly in between. Maximum spacing between brackets is 20 feet.

10 Installation: Step 4 Lay out brackets along ridge lines at required spacing Each ridge segment requires a minimum of two brackets, one at each end

11 Installation: Step 5 (New Construction) Install wood structural panel roof sheathing per the requirements of the building code and the building designer

12 Prior to installing the Shear-X brackets, the installer must remove 1" to 1½" of sheathing on both sides of the ridge leaving 6" to 12" at each end of the ridge uncut Installation: Step 6

13 Installation: Step 7 Center the Shear-X bracket on the ridge line Ensure each end of the bracket aligns with the roof framing below.

14 Attach the bracket with 10d (0.131"x 3") nails in each prepunched hole along the ridge line Installation: Step 8

15 Bend bracket tightly to the top of the roof sheathing to conform to the pitch of the roof Installation: Step 9

16 Secure each end of the bracket through the roof sheathing to the rafters/trusses with a minimum of four (0.131 x3 ) nails Install nails in the prepunched holes closest to the ridge Make sure bracket remains flat against the roof sheathing Installation: Step 10

17 Installation: Step 11 Complete the attachment of the bracket by installing the remaining nails. Be sure to nail directly into the rafters/trusses and NOT just the sheathing.

18 Roll out and install ridge vent along ridge line of roof according to manufacturer s installation instructions Installation: Step 12

19 Install the ridge cap shingles according to shingle manufacturer s instructions Installation: Step 13

20 Additional Resources