**Strength Characteristics of Joists:**
– Joists must support anticipated loads meeting building code standards.
– Joist depth is crucial for stability, with deeper joists reducing stress and deflection.
– Lateral support like dwang, blocking, or strutting enhances stability.
– Approved formulas and load tables help calculate required joist depth.
– Engineered wood products like I-joists offer increased strength by expanding depth.
**Types of Joists:**
– Double floor uses joists supported by larger timbers.
– Traditional timber framing has single or double floor configurations.
– Binding joists perpendicular to gable roof ridge with bridging joists.
– Summer beams in ceilings carry joists, which can be flush or exposed.
– Exposed joists below ceilings are known as naked flooring or articulated.
**Connections to Supporting Beams:**
– Joists join supporting beams through various methods like lodging or tenoning.
– Different joints like chase mortise, L-mortise, and short joist are used.
– Ground level joists are placed on the foundation with sill on top in Dutch-American work.
– Joists do not tie beams together but may have pins for tension.
– Joists on ground floors are sometimes supported by poles or sleepers.
**Related Concepts and Resources:**
– Related terms include beam, framing, girder, purlin, rafter, and truss in relation to joists.
– Wikimedia Commons has joist-related media for further reference.
– References to construction technology and a glossary of architectural terms are available.
– A comparison of joist hangers, end-nailing, and toe nailing for decks is provided for clarity.
**References:**
– Fleming, Eric. Construction technology: an illustrated introduction.
– Emmitt, Stephen, R. Barry, and Christopher A. Gorse. Barrys advanced construction of buildings.
– John Henry Parker’s glossary of architectural terms.
– Oxford English Dictionary defines joist.
– Comparison of joist hangers, end-nailing, and toe nailing for decks.
A joist is a horizontal structural member used in framing to span an open space, often between beams that subsequently transfer loads to vertical members. When incorporated into a floor framing system, joists serve to provide stiffness to the subfloor sheathing, allowing it to function as a horizontal diaphragm. Joists are often doubled or tripled, placed side by side, where conditions warrant, such as where wall partitions require support.
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Joists are either made of wood, engineered wood, or steel, each of which has unique characteristics. Typically, wood joists have the cross section of a plank with the longer faces positioned vertically. However, engineered wood joists may have a cross section resembling the Roman capital letter "I"; these joists are referred to as I-joists. Steel joists can take on various shapes, resembling the Roman capital letters "C", "I", "L" and "S".
Wood joists were also used in old-style timber framing. The invention of the circular saw for use in modern sawmills has made it possible to fabricate wood joists as dimensional lumber.
Definition from ChatGPT:
Joist:
A joist is a horizontal structural member that supports the floor or ceiling of a building. Joists are typically made of wood, steel, or concrete and are spaced evenly to provide structural support for the floors and ceilings above.