Girder vs. Girt — What's the Difference?

Girders serve as the main horizontal supports in building and bridge construction, designed to bear large loads. They are key components in the framework, often supporting beams and other structural elements. Girders can be made from various materials, including steel, concrete, or wood, and are crucial for the structural integrity of large constructions. On the other hand, girts are horizontal structural elements used primarily in metal buildings or similar constructions, acting as secondary supports. They provide lateral support for wall cladding and can be integral to the stability of the structure, but they do not carry the same load as girders.

While girders are typically larger and bear more weight, functioning as the backbone for floor and roof structures, girts are smaller and serve to stiffen the walls and provide attachment points for exterior materials. Girders often require significant engineering and design work, given their critical role in the overall structure. In contrast, girts, though important, are part of a system of secondary supports and are standardized in many metal building systems.

In terms of installation and placement, girders are positioned to distribute weight and loads across a wide area, often spanning large distances and requiring precise calculations to ensure safety and stability. Girts are installed between columns or piers and are spaced at intervals determined by the building design, primarily focusing on the requirements for wall stability and cladding attachment rather than load-bearing capacity.

The terminology and specific uses of girders and girts reflect their roles in construction. Girders are often discussed in the context of major infrastructure projects, skyscrapers, and large commercial buildings, where their function and design are critical to the project's success. Girts, while also important, are more specific to certain types of construction, like metal buildings and structures where wall cladding is a significant consideration.

The material composition of girders and girts also differs based on their functions. Girders, needing to support significant weight, are constructed from materials with high strength and durability. Girts, while still made from sturdy materials, have specifications that prioritize ease of installation and compatibility with cladding materials, reflecting their role in the structural ensemble.