Girts are horizontal structural members used in the construction of buildings with metal cladding, particularly in the context of pre-engineered metal buildings and steel-framed structures. They are essential components for supporting and bracing wall panels. Here’s a detailed description of girts in structural steel detailing:
Table of Contents
1. Definition:
- Girts are horizontal members that run parallel to the sidewall of a building. They are attached to the main structural frame (such as columns or wall studs) and provide support for the exterior wall panels.
2. Types of Girts:
- Z Girts: Shaped like the letter “Z” when viewed in cross-section, these girts are commonly used in metal building systems. They offer strength and are often easy to install.
- C Girts: Shaped like the letter “C,” these girts are also common in metal building construction. They provide a flat surface for attaching wall panels.
3. Material Specifications:
- Girts are typically made from cold-formed steel sections, and their material specifications are determined based on design requirements. Common specifications include the thickness and grade of the steel.
4. Size and Dimensions:
- The size and dimensions of girts depend on factors such as the design loads, building height, and the spacing of columns or wall studs. Girts must be appropriately sized to support the loads imposed by the wall panels.
5. Connection Details:
- Detailing includes information about how girts are connected to the main structural frame, whether it’s through welding, bolting, or other connection methods. Proper connection details are crucial for the overall stability and load-bearing capacity of the structure.
6. Spacing:
- The spacing between girts is determined by factors such as the type of wall panels used and the design wind loads. Proper spacing ensures that the girts adequately support the wall panels and resist lateral loads.
7. End Conditions:
- Details about how girts are terminated or connected at their ends are specified in the detailing process. This includes information about corner conditions and connections to other structural elements.
8. Bracing:
- Girts may serve a bracing function, contributing to the overall lateral stability of the building. Detailing includes information about the type and location of bracing elements.
9. Openings:
- Girts may need to accommodate openings for doors, windows, or other architectural features. Detailing provides information on how to modify or reinforce girts around these openings.
10. Marking and Identification:
- Each girt is typically marked with a unique identifier for easy identification during construction. This includes information about the material, size, and any other relevant details.
In structural steel detailing, girts are crucial components for ensuring the stability and integrity of the building envelope. Detailed drawings and specifications for girts are created to guide fabrication and construction processes accurately.