Ever wondered what those bars are on the roof or floor? BAR JOIST is framing members that support low-slope or flat ceilings and floors. Their makeup includes a pair of parallel chords connected by a series of intersecting supports known as the web.

bar joist of a company

Bar Joist 101

How Are They Identified?

To classify various kinds of bar joists, many industry professionals and manufacturers utilize an alpha-numeric identification scheme, such as 12K8. This code is frequently stamped or printed on the joist, making it easier for purchasers and installers to recognize the joist.

The first character of the code is a number, which stands for the joist’s depth in inches. Following each depth measurement is a set of letters that denotes the joist design. Standard joists are represented by a “K,” while a “CS indicates joists made to support concentrated loads.” Joists that are very long, deep, or enormous are identified using different specialized labels.

How Are Joists Designed?

Joists are manufactured in a controlled environment and designed per project basis, preventing weather issues from affecting or holding up production. Manufacturing in this manner creates an opportunity for an improved economy. This is because the manufacturer can adjust the material makeup and sizing to benefit from the current material pricing.

Moreover, material price volatility and availability can impact how joists are designed.

bar joist in a building

What Are the Bar Joist Series?

Bar joists are manufactured in several different series, with each series designed for specific spanning loading purposes.

  • K Series – These are standard-sized joists used for typical uniform loading applications. They range in depth from 10 inches to 30 inches and span 260 feet in length.
  • KCS Series – These types are designed for non-uniform or constant shear loads. Hence, where the “KCS” comes from and the designation. These joists would typically be used in applications with point loads to accommodate such things as a rooftop mechanical unit. The only difference between a K and KCS joist is that the latter can accommodate constant point load, such as roof-mounted equipment.
  • LH Series – This type, commonly known as long span series, is mainly applied where spans more significant than 60 feet are required.
  • DLH Series – Shorter span situations needed lighter loads with continuous shear and moment demand for the usage of DLH Series joists. These joists can support spans that wood systems cannot. Also, because of their lightweight design, they are far less expensive than steel beams. DLH Series joists can span up to 60′ and have a depth range of 10″ to 30.”

Why Use Bar Joints?

Modern roofing and flooring systems rely heavily on joists and joist girders. These are efficient, cost-effective alternatives that can significantly increase the value of your construction, whether you’re creating a single or multistory building.

These joists are made to work in tandem with the concrete slab placed on top of the steel deck to create a very practical floor system. Likewise, to assist the architect and engineer in realizing a unique vision, a good joist company can design and produce customized joists, including gable joists and barrel joists.

In addition to being an essential structural component of the building, these joists can also be of significant architectural value.

Why Not Use Traditional Beams?

In comparison to conventional beams or girder construction, bar joists have a number of benefits. The majority of joist systems are factory-prefabricated and arrive at construction sites prepared for usage—these aid in accelerating construction and lowering labor costs.

Additionally, compared to most structures framed on-site, a pre-manufactured bar joist is built with greater precision. This increases building security and produces a stronger, more stable structure. The overall amount of waste is also decreased by joist construction, which lowers disposal and shipping expenses.

Is There a Drawback?

The high expense of the joist in comparison to stick framing is one of the main disadvantages of bar joist construction. Stick framing is still less expensive upfront even if labor and disposal savings frequently outweigh this expense. There is also a chance that design and engineering time may be lost because joists must be pre-manufactured to precise design requirements.

How Much Does It Cost?

The price for bar joists may change based on the size and complexity of your project. When thinking about bar joists, keep in mind that many manufacturers base their prices on the amount of square footage utilized.

Most bar joists are made of steel. Typically, these cost between $300 and $500 per square foot. The costs might be lower if your construction project occupies a smaller space, like a shed or small building. Your bar joists may be available for $100 per square foot.

You should also consider any shipping or customizing fees that may apply. Remember that the materials’ weight may affect the cost as well. The price can go up if you demand supplies that can handle heavy use. Find out which manufacturers best meet your needs, whether you’re on a tight budget or require a different price structure.

bar joist in a factory

Get the Best Bar Joist!

At Miami Metal Deck, we have a full range of joists, including standard joists, joist girders, and composite joists, following the standards established by the Steel Joist Institute (SJI). Call us!