What is Difference Between Joist and Beam?
While the terms joist and beam are often used interchangeably, you should know the difference between the two structural elements. The latter serves as the main load-bearing beam in a home, while the former is used to support the floor joists. In general, the strength-to-weight ratio of a joist is higher than that of a beam.
The primary difference between the two is the size of the component. Girders are the largest, horizontal members of a building, while beams are smaller but serve similar functions. A girder is more commonly used in commercial construction. Beams are used for a variety of purposes, but are often considered secondary to joists.
The most common use for a beam is in residential construction. A beam can support as much as 300 pounds of weight, while a joist can hold up to 900 pounds. Beams are more versatile than joists. They can span a longer distance than a joist. In addition, beams are generally paired and/or tripled.
A beam is used in construction projects to transfer the weight of a floor or roof. It is more substantial than a joist, and it will transfer the load to the vertical elements of a building. Beams are typically made of steel, combined dimensional lumber, or engineered wood. While these materials are stronger than wood, they are also more expensive. Nevertheless, wood beams are often used for small projects and for smaller buildings.
While beams and joists serve similar roles, they are slightly different. While joists support floor loads, beams support the main weight of the building, which is why beams are often used in multi-storey structures. Regardless of their function, these two types of construction components can work together or independently.
In general, joists are lighter than beams, but they still support the bulk of the home’s weight. Beams are usually made of dimensional lumber, and can be the same size or smaller than joists. They are usually covered by sheathing (usually plywood) to ensure strength. This sheathing helps reinforce the joists and prevent them from flexing.
There are many types of joists. In the U.S., these types are often called floor joists or articulated joists. In the past, these joists were often planed smooth or beaded to make them look more appealing.
Floor joists support the floor, and whatever else is placed on it. The choice of the right type of joist depends on your project requirements. Use a span table to calculate the size of joists you need for your project. If you’re unsure of how many you’ll need, you can consult a structural engineer.
A joist must be at least sixteen inches from a wall. Similarly, the distance between two beams must be at least 24 inches apart. This distance is based on how much weight is on each joist.
