text.skipToContent text.skipToNavigation

Top-Plate-to-Stud Rotation Restraint

The roof-structure-to-top-plate connection induces eccentric loads to the top plate. This will require a top-plate-to-stud connection to continue the load path and prevent torsional rotation of the top plates. Simpson Strong-Tie offers a variety of product options to resist the rotational forces from the roof structure.

Top Plate to Stud Lineup
Truss-to-plate connections not shown for clarity. However, they need to be installed on the same side of the wall as plate-to-stud connectors.
AC391 Criteria Section AC391 Requirement
3.2.2.3 Top-plate torsion (rotation) must be prevented due to offsets between the point of load application, such as hurricane ties at the sides of the top plates and load resistance (rods at the center of the top plate for example). This can be accomplished by providing a positive connection from the top plate to stud on the same side of the wall as the roof framing to wall connection.
Stud-to-Plate Tie Reaction
Stud-to-Plate Tie Reaction
Top-Plate Rotation Failure Due to Uplift
Top-Plate Rotation Failure Due to Uplift
Ultimate Failure of Top Plate in Pure Bending Due to Rotation Restraint
Ultimate Failure of Top Plate in Pure Bending Due to Rotation Restraint

When connection hardware between the roof framing members and the wall top plate induces eccentric loading about the centerline of the top plate, Simpson Strong-Tie® top-plate-to-stud connectors are the optimum installation solution to prevent top-plate rotation as shown in illustration below. The top-plate-to-stud connectors must be installed on the same side of the top plate as the roof-to-wall connectors. Connector models must be selected and installed in a manner that does not induce significant tension stresses perpendicular to the grain of the wood top-plate members.

Required Top Plate Rotation Restraint Connection Force1

Required Top Plate Rotation Restraint Connection Force

For SI:1 inch = 25.4mm

  1. The top plate-to-stud connection used to restrain top plate rotation must be installed on the same side of the wall as the roof-to-top plate connection.
Top-Plate Rotation Restraint Connection Force
Top-Plate Rotation Restraint Connection Force

For hurricane tie components that can connect top plates to studs to resist rotation refer to the High Wind–Resistant Construction Application Guide (F-C-HWRCAG) or pp. 324–325 of the Wood Construction Connectors catalog.

F-C-HWRCAG16 – High Wind-Resistant Construction Application Guide
F-C-HWRCAG16 – High Wind-Resistant Construction Application Guide
Get the Guide