What is the maximum span of 2×8 floor joist

The floor joist is a wood product and it comes in different quality, its quality is divided into 3 categories Grade 1, Grade 2, and Grade 3. What is the maximum span of 2×8 floor joist? It depends upon the grades of the floor joist. Grade 1 floor joist is the most trusted and premium quality floor joist.

Through this article, we will see the following things

  1. What is the maximum span of a 2×8 floor joist?
  2. How far can I span a 2×8 floor joist?
  3. How far can a 2×8 floor joist span without any support?
What is the maximum span of 2×8 floor joist

What is a 2×8 floor joist?

A 2×8 floor joist is a horizontal structural member that supports a floor. These are basically made of wood, and can also be made of steel and concrete. There are different depths of floor joists that are used in deck floor construction they are 2×6, 2×8, 2×10, 2×12 and 2×14. Which are an important part of any building’s construction.

Their main function is to provide support for the weight of the floor and to help in distributing the overall load. It also helps to prevent sagging and deflection of the floor. Floor joists are widely used in a variety of buildings like residential, commercial, and industrial buildings. Their uses can also be seen in bridges, decks, and other structures. The benefit of using a 2×8, 2×10, 2×12 and 2×14 floor joist.

  1. Strong:- The floor joist is very strong and also supports a lot of weight.
  2. Stiff:- Floor joist resists deflection very well as they are very stiff in nature.
  3. Versatile:- They are very versatile as they can used in a wide variety of applications.
  4. Durable:- Floor joists are also very durable as they last for many years.

Joists are made of different species of wood mainly southern yellow pine & Douglas fir and are categorized as Grade-1, Grade-2, and Grade-3. Southern yellow pine is the strongest species of wood that spans more distance as compared to other species of wood.

Grade-1 lumber has higher strength than other grade lumber cause they have fewer knots. The spacing between floor joists for different sizes is kept at 12 inches, 16 inches, and 24 inches. The standard spacing between 2-floor joists is 16 inches.

What is the maximum span of 2×8 floor joist?

The maximum span of a 2×8 floor joist is 15 feet 10 inches at 12 inches on center spacing. The same size floor joist can span up to 14 feet 5 inches when at 16 inches on center spacing. When it is at 24 inches of OC, it can 2×8 floor joist span up to 12 feet 4 inches.

This only applies to the floor joist made of structural grade Douglas Fir-larch at 10 PSF dead load & 30 PSF live load. A 2×8 floor joist span of Douglas larch floor can allow for a maximum span of 15 feet 10 inches at 12 inches from center to center, 14 feet 5 inches by 16 OC, or 12 feet 4 inches at 24 inches.

How far can span 2×8 floor joists?

A 2×8 floor joist can span as far as 13 feet and 8 inches. This is based on using the No.2 southern yellow pine lumber that is spaced at 16 inches in the center. When a stronger wood like No.2 Douglas fir larch is used for the same size floor joist and spacing we can reach about 14 feet.

How far can a 2×8 floor joist span without any support?

A 2×8 floor joist can span up to 14 feet and 1 inch without any kind of support by using the No.2 Douglas fir lumber spaced at 16 inches in the center. And total load at 40 PSF at 12 inches on center spacing the same-size floor joist can span up to 15 feet & 7 inches. At 24 inches OC, a 2×8 floor joist has a maximum span of 11 feet 6 inches.

You should also read this:

Conclusion

We have now come to know from this article that the maximum span of a 2×8 floor joist is 15 feet and 10 inches at 12 inches on center spacing. At 16 inches on center spacing, the 2×8 floor joist can span up to 14 feet and 5 inches.

Leave a Comment