Basic Floor Joist System

69 chapter 4 floor construction woodframe floor systems and concrete slab on grade floors are discussed in this chapter.

Basic floor joist system. Used to combat shear forces provides safe work environment and provides nail able surface for the finish floor. Open web trusses with wood webbing held together with metal plates. I joists have major advantages in high volume construction with standard layouts. Trus joist tji joists are a key part of making a high performance floor.

Floor joists are typically 2 by 8s 2 by 10s or 2 by 12s. Sits on top of sill plate. Dimensional lumber is a common flooring system with three main components. Apa performance rated i joists pris are manufactured in accordance with pri 400 performance standard for apa ews i joists form x720 this performance standard provides an easy to use table of allowable spans for applications in residential floor construction allowing designers and builders to select and use i joists from various member manufacturers using just one set of span.

This article teaches you how to build a floor for a house on a concrete foundation. The dimensional stability of tji joists help them resist warping twisting and shrinking that can lead to squeaky floors. This sample table gives minimum floor joist sizes for joists spaced at 16 inches and 24 inches on center o c for 2 grade lumber with 10 pounds per square foot of dead load and 40 pounds of live load which is typical of normal residential construction. These include the subfloor joists and beam.

True floor joist span calculations can only be made by a structural engineer or contractor. Wood i joists with dimension lumber top and bottom chords and osb web. Joist spans and spacing are determined by engineering that is published by the manufacturer. Joists are the horizontal members of the floor.

The beam provides added strength at the middle point and spans the distance between the two sides of the floor. Two types of engineered joists are most frequently used in floor systems today. Like studs spaced out at equal distances. Framing a floor using i joists.

Some newer homes have manufactured i beam shaped joists. Tji joists are lightweight and come in long lengths which makes them faster and easier to install than traditional framing and saves you both. Although cold formed steel framing for floor systems also is permitted by the irc it is not covered here. This is because they are.

The three main types of floor joists used in home construction are solid lumber i joists and open web floor trusses. Ceiling joists are usually 2 by 6s or sometimes 2 by 4s if it is an older home. Joists run perpendicular to the beam with a center point resting on the support. They wrap around the joists.

A floor s framework is made up mostly of wooden joists that run parallel to one another at regular intervals. Each type of floor joist offers its own unique benefits and drawbacks which is why those working in carpentry all tend to have their own favorite floor joist option though they are still required to be well versed in each type of floor framing. This framing system can also be used for framing storage shed floors this floor framing system is typical over basements and crawl spaces.