Covered Bridge Terminology

Covered Bridges are pieces of history. They are often important transportation links, centers, and points of pride for communities.

Source

Covered Bridge Manual, U.S. Department of Transportation, Federal Highway Administration 2005

  • Shelter Panel Covering

    These panel protect the truss system from windborne rain and from water that is splashed from vehicles entering the bridge. Other terms include interior end siding or false door (2005, p. 17).

    Goodpasture Covered Bridge

  • Siding

    The type of covered bridge sides is based on the owner, designer, or builder. Windows provide additional light to facilitate safe daytime passage. They also provide fishing access. While the windows expose the surrounding timber to windborne rain, significant rot is rare (2005. p. 68).

    Hannah Covered Bridge - open sides

  • Windows

    Many bridges have windows only on one side. Bridges without windows were often vandalized to create fishing access, so restoration often included adding windows (2005, p. 68).

    Office Covered Bridge

  • Stringers

    Stringers are “longitudinal beams supporting load from the decking to the floor beams” (2005, p. 55). North Fork Yachats Covered Bridge has four stingers providing support for vehicles as they transport goods.

    North Fork Yachats Covered Bridge

  • Truss Diagonal

    Let’s be honest; I am not an engineer. I am learning-and-growing which leads me to believe this is a diagonal truss but some diagrams have it listed as a brace chord. I appreciated how this image showed the interplay between the panels and the support systems.

    Fisher School Covered Bridge

  • Bridge Deck

    That marvelous thump-thump-thump sound of a covered bridge is tires crossing over bridge decking. “Floor beams, floor joists, and floor plank comprise the bridge deck” (2019, p. 83).

    Fisher School Covered Bridge

  • Steel Fish Plates

    Fish plates can be wooden or steel. Original builders used wooden fish plates that reinforced butt joints. The two pieces of wood are clamped together to help share the tension forces (2005, p. 147).

    Coyote Creek Covered Bridge

  • Wood Treatment

    “Three groups are responsible for most of the damage: powder post beetles, termites, and carpenter ants” (2005, p. 221). Prevention is key to ensuring covered bridges are not tasty treats for bugs. The 2005 Covered Bridge Manual by the U.S. Department of Transportation features multiple pages on appropriate treatment.

    Coyote Creek Covered Bridge

  • Height Requirements

    It is important for drivers to be aware of their vehicle height to ensure covered bridges are not damaged.

    Coyote Creek Covered Bridge