Cold-formed steel framing has become a popular choice in construction projects, with contractors now more often choosing cold-formed steel over traditional wood framing. But what exactly are the common types, the benefits, and what should you consider when ordering from a manufacturer? In this comprehensive guide, we’ll explore everything you need to know so you can order the right materials. We’ve also included a helpful list of resources and technical guides that you can reference when embarking on your next cold-formed steel framing project.
Cold-formed steel (CFS) refers to thin steel that has been rolled to less than 1/8th of an inch and bent into a specific shape without being reheated. It’s often found in appliances, cars, and laptops. Cold-formed steel framing, however, is used in construction where thin sheets of steel are typically formed into shapes to take advantage of its large strength to weight ratio. The most commons shapes are C, Z, U, or hat channels.
Cold-formed steel is a unique building material. With most materials (wood, steel, concrete, etc.), the designer determines the elastic or plastic limit of the material and backs off from that limit by some factor of safety. Cold-formed steel is limited by buckling before it experiences elastic or plastic limits. Buckling controls most of the design aspects.
A stud refers to cold-formed steel that has been formed into a C-shape with a lip return. These are typically used as a vertical element in the framing of a wall or column/post. Deeper stud sections can be used for floor joists, roof joists, and beams.
A track section will often cap the bottom and top of a steel stud wall. These products are U-shaped and do not have a lip return to allow the stud to seat inside the track.
This is a smaller U-shaped product that goes through the web knockout of each stud for bracing or will often be used to support ceiling framing with hanger wire. It’s important to note: standard studs have knockouts that are oval shaped holes at a periodic spacing used for electrical conduit or plumbing; a U-channel can pass through these knockouts and tie studs together for bracing.
This refers to a “hat-channel” type of CFS that is often applied to the face of wall or bottom of ceiling in order to provide a wedge or spacing element (otherwise known as furring) to the sheathing. This can help reduce sound transmission or improve fire resistance.
This piece of CFS is a large angle, or L-shaped, and is positioned on top of the wall top track to act as a simple header. They span across openings to help transfer the load over a door or window onto jamb studs. L-headers are less common in construction.
Straps are 2 to 12-wide thin sheets of steel used for tension loads. They will most often be found in wall bracing or shear walls.
There are many reasons why you should consider CFS framing if you’re constructing a building, including:
Training for CFS is very similar to wood construction. Framers can apply existing skills with new CFS framing tools, which include:
Another reason to consider using cold-formed steel is the potential for considerable cost savings. Like wood framing, the material costs for cold-formed steel are per unit (pound or board foot), but 70% of the cost in construction is the labor. The high strength-to-weight of steel allows for fewer members to be used in assemblies. For example, we often use one stud jambs vs. a king and a jack stud for wood.
Here are a few ways cold-formed steel can reduce construction costs:
The owner of a building (new or under renovation) will typically hire a design team, including an architect and structural engineer, to produce construction drawings that describe the intent of the project. As an example, the structural engineer will likely size columns and beams, but is often not as concerned with the methodology of how those beams will be connected if the connection meets the design loads. In some cases, the beams could be welded; in others, they could be bolted together.
Construction drawings speak to the intent of the building and do not necessarily dictate specificity of means and methods, whereas shop drawings are more product-specific and describe how the structure will be built and how it meets the required design parameters. (For example, construction drawings might size a joist as a 1000S200-68 at 16” o/c and give the loads, but the number of screws and connectors would be specified in the shop drawing.)
It is important to keep in mind that building codes require that cold-formed steel framing, whether interior or exterior, to be designed by a design professional (a licensed architect or engineer.) In some cases, the structural engineer or architect who produced the construction drawings may choose to take responsibility for the CFS framing and may not require shop drawings — but this is rare.
In most cases, the structural engineer — otherwise known as the engineer of record — provides performance specifications, such as the ability to handle a specified wind load. The structural engineer will then rely on a specialty structural engineer, such as a cold-formed steel engineer, to design the framing elements and produce a set of shop drawings. The specialty engineer is often hired by the subcontractor responsible for the cold-formed steel framing.
In any construction project, it’s essential to review architectural specifications, ask for clarification if needed, and know who is responsible for which components of the job. It is too late to find out that you need shop drawings when you begin to mobilize for a job.
There are certain industry standards when it comes to the manufacturing of cold-formed steel stud and joist framing. This means that, for the most part, you will find similar products among manufacturers.
There are, however, some pitfalls to be aware of. Not all manufacturers use the same grade of steel for their studs. For example, 16 gauge material might be stronger for one manufacturer than another, and some manufacturers may have better quality assurance/quality control processes than others.
The specifier should consider the project’s location and use when specifying the stud galvanizing thickness. While G60 is common for exterior stud walls, structures in a high moisture environment (pools) or near a high salt area (ocean) might consider a thicker coating, such as G90. Even thicker coatings are possible, but you may be required to purchase a whole coil of steel.
When it comes to angles and clips, premanufactured connectors by Clark Dietrich, Simpson StrongTie, and The Steel Network are the most common in the industry. However, they are all proprietary and have different capacities and uses. Equivalency charts should be used with caution.
It’s also important to remember that unlike wood framing, you can order CFS studs to specific lengths. Precut studs can save a lot of time on a project, but they require careful planning.
Many projects are bid and won prior to the involvement of a specialty engineer. Bidders can avoid costly mistakes by working with a specialty engineer during the bidding phase to get preliminary sizes and/or an understanding of costly details.
In this section, learn more about what contractors should consider when submitting cold-formed steel design drawings and how to identify potential costly details.
Are you looking for codes, standards, and more industry information? We’ve compiled a list of cold-formed steel framing technical guides and resources, which include:
With 25 years of structural engineering experience, Tony has provided structural design and analysis for a variety of institutional, commercial, industrial and residential projects. He has specialized expertise in the design of coastal structures, cold-formed steel, and building envelopes. In 2009 he was awarded the New Hampshire Young Engineer of the Year Award. At this time, he served as the President of the Structural Engineers of New Hampshire, advocating for structural engineering related issues in New Hampshire and promoting the growth of the industry.
In 2009 and again in 2011, Tony was elected to the Portsmouth City Council. During this time, he advocated for sustainable budgeting, transparent government, good schools, and infrastructure improvements. In 2011, Tony was recognized by the New Hampshire Union Leader and the Business Industry Association of New Hampshire as one of the “Forty under 40” leaders making a difference in the state. You can contact Tony at tonyc@mcclurevision.com.
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