Engineered Faming Details for Light-gauge Steel

Engineered Faming Details for Light-gauge Steel CFS-SOLID BLOCKING DETAIL

We here are US Frame Factory frequently support our clients with engineering advice and material take-offs. We have become familiar with a lot the various framing details through this process. Here are some common ones useful for residential and commercial construction.

Acronyms will be used in this article: CFS (Cold Formed Steel) and LGS (Light-gauge Steel)

Why do you need engineering details for metal framing?

Engineering details are crucial for metal framing for several important reasons:

1. Structural Integrity and Safety:

  • Load Calculations: Engineers analyze the types of loads a structure must withstand (live load, dead load, wind load, seismic load, etc.). This determines the necessary size, gauge (thickness), and spacing of framing members for safe and code-compliant support.
  • Strength and Stability: Metal studs have specific strength characteristics. Engineering details ensure the framing is designed properly to prevent failures like bending, buckling, and twisting under anticipated loads.
  • Connections: Proper connection details (screws, welds, etc.) between different framing members ensure they transfer loads effectively, maintaining the structure’s integrity.
  • Deflection Limits: Engineers calculate acceptable amounts of deflection (bending) in metal framing for floors, walls, and ceilings. This prevents issues like cracked finishes or misaligned doors and windows.
  • Corrosion Protection: Details might specify proper coatings or material selection for metal framing used in corrosive environments.(Important to note that in Miami-Dade county building codes require G90 metal stud coating as opposed to G60)

2. Building Code Compliance:

  • Prescriptive vs. Performance-Based Design: Building codes may have prescriptive requirements (e.g., using a specific stud size for a certain span). However, engineers often use performance-based calculations to prove alternative designs meet code standards.
  • Standards and Specifications: Engineering details adhere to standards set by organizations like the American Iron and Steel Institute (AISI) and the American Society for Testing and Materials(ASTM), ensuring safe and reliable construction.

3. Optimization and Cost-Effectiveness:

  • Material Selection: Using engineering analysis, the project can select the most appropriate and cost-effective metal stud gauges and types for specific load requirements. This avoids unnecessarily oversizing framing members.
  • Design Innovations: Engineering can help introduce new framing configurations that optimize material usage while still ensuring structural adequacy.

When you do not need engineering Details

It’s important to note that not all metal framing projects require engineering details. Simple, non-structural applications like interior walls with minimal load might not necessitate involving an engineer. However, whenever structural integrity, compliance, or complex design are involved, consulting with a qualified engineer is highly recommended for a safe and successful project.

Window Opening with Header

Engineered Faming Details for Light-gauge Steel Window Opening with Header
This is a common structural header in steel framing. Used for doors and windows.

CFS Boxed Header to CFS post Detail

This is the detail for constructing a load-bearing light-gauge steel beam. The span depends on the web sizing of the stud and the gauge thickness.

WEBBED BEAM TO CFS POST

Engineered Faming Details for Light-gauge WEBBED BEAM TO CFS POST This is the variation of a the door/window header, opting for a small truss like configuration.

This is the variation of a the door/window header, opting for a small truss like configuration.

ROOF TRUSS TO STEEL BEAM CONNECTION DETAIL

Engineered Faming Details for Light-gauge Steel ROOF TRUSS TO STEEL BEAM CONNECTION DETAIL
This is for fastening light gauge steel roof trusses

This is for fastening roof trusses steel beams. The combination of structural steel and LGS trusses are often used on large commercial buildings with non-flat roofs like schools.

ROOF TRUSS TO EXTERNAL WALL CONNECTION

Engineered Faming Details for Light-gauge Steel ROOF TRUSS TO EXTERNAL WALL CONNECTION
This detail is for attaching trusses to walls. Often all that’s needed is a clip and multiple screws. In windy areas sometimes hurricane straps are needed also.

SPLICE CONNECTION OF PURLIN MEMBER

Engineered Faming Details for Light-gauge Steel SPLICE CONNECTION OF PURLIN MEMBER
For a soffit overhang used in combination light-gauge steel trusses with an overhang purlin.

STUD TO SILL/ BOTTOM TRACK CONNECTION

Engineered Faming Details for Light-gauge Steel Engineered Faming Details for Light-gauge Steel STUD TO SILL/ BOTTOM TRACK CONNECTION
This is the most common detail used in light gauge steel framing. In this case the engineer elected to have (2) #10 screws on each side of the track and stud.

LATERAL BRACING TO STUDS CONNECTION DETAILS

Engineered Faming Details for Light-gauge Steel Engineered Faming Details for Light-gauge Steel LATERAL BRACING TO STUDS CONNECTION DETAILS

Almost every commercial job with load-bearing walls has a requirement for lateral bracing. Two two primary uses for lateral bracing is.

  • Rotation (Twisting): Studs can twist along their long axis (also called torsional buckling). This dramatically decreases their ability to carry vertical loads.
  • Minor-Axis Bending: Studs can bend sideways, across their narrower dimension. This is different from the intended bending direction along their wider side.

Metal Stud Bridging Detail

Engineered Faming Details for Light-gauge Steel Metal Stud Bridging Detail

Metal stud bridging serves the same purpose as CRC bracing. Allowing prevention of rotation twisting and minor-axis bending.

Metal Stud Header w/ Schedule

Engineered Faming Details for Light-gauge Steel Metal Stud Header w/ Schedule

Engineers specify a header schedule based on window opening sizes. A header schedule is a crucial document that specifies the design and installation details of headers. Headers are essentially horizontal beams used to span openings in walls, supporting loads from above like floor joists, beams, or even additional wall sections. The header schedule ensures these openings are properly supported and maintain structural integrity. You can see the header size and gauge increases as you opening span increases.

Stud wall Bracing from Metal Deck

Engineered Faming Details for Light-gauge Steel Stud wall Bracing from Metal Deck

Often you have to brace wall after building a drop ceiling. This detail shows how to have studs at an angle to supply the bracing in conjunction with metal decking.

Parapet detail with Bracing

Engineered Faming Details for Light-gauge Steel Parapet detail with Bracing

Parapet bracing is something that usually played by eye on the job site. However you will always need a clip to attach to the ground and a structural peace to offer support.

Parapet detail with Bracing over Steel beam

TYPICAL PRECAST PLANK ON INTERIOR STEEL STUD WALL

TYPICAL PRECAST PLANK ON EXTERIOR WALL

NON BEARING WALL BRACING AT PRECAST PLANK

CFS-SOLID BLOCKING DETAIL

CFS-BRIDGING DETAIL

CFS-RIM TRACK TO CMU CONNECTION

CFS-RIM TRACK TYPICAL DETAIL

CFS-DIAGONAL STRAP SHEAR WALL DETAIL

CFS-GUSSET PL BOTTOM

CFS-GUSSET PL TOP

Additional Resources

Building Hotels and Apartments Out of Metal Studs
Engineered Metal Trusses
Frequently asked Metal Stud / Steel Framing Questions

Leave a Reply

Your email address will not be published. Required fields are marked *