Basic Floor Joist System

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.

Basic floor joist system.

Used to combat shear forces provides safe work environment and provides nail able surface for the finish floor. They wrap around the joists. This article teaches you how to build a floor for a house on a concrete foundation. Framing a floor using i joists.

Two types of engineered joists are most frequently used in floor systems today. 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. Rather the reader is referred to the aisi standard for cold formed steel framing prescriptive method for one and two family dwellings aisi 2001 for guidance. A floor s framework is made up mostly of wooden joists that run parallel to one another at regular intervals.

Some newer homes have manufactured i beam shaped joists. Open web trusses with wood webbing held together with metal plates. Although cold formed steel framing for floor systems also is permitted by the irc it is not covered here. Subflooring is usually plywood.

The dimensional stability of tji joists help them resist warping twisting and shrinking that can lead to squeaky floors. I joists have major advantages in high volume construction with standard layouts. Tji joists are lightweight and come in long lengths which makes them faster and easier to install than traditional framing and saves you both. Dimensional lumber is a common flooring system with three main components.

Like studs spaced out at equal distances. Ceiling joists are usually 2 by 6s or sometimes 2 by 4s if it is an older home. True floor joist span calculations can only be made by a structural engineer or contractor. Floor joists are typically 2 by 8s 2 by 10s or 2 by 12s.

This framing system can also be used for framing storage shed floors this floor framing system is typical over basements and crawl spaces. The three main types of floor joists used in home construction are solid lumber i joists and open web floor trusses. 69 chapter 4 floor construction woodframe floor systems and concrete slab on grade floors are discussed in this chapter. Trus joist tji joists are a key part of making a high performance floor.

Wood i joists with dimension lumber top and bottom chords and osb web. These include the subfloor joists and beam. 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.

Joist spans and spacing are determined by engineering that is published by the manufacturer. Sits on top of sill plate. 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.