Selection of Frame Column Depths

SidePlate® connections work for both square columns (e.g. W10x, W12x, W14x, HSS, Box) or rectangular (e.g. W18x, W21x, W24x to W36x). A rectangular column is more economical for moment frames, so we try to use these where the architecture allows for it. Note that SidePlate® is not limited to rectangular columns, though.

Figure A1 - Plan View Comparison of Column Depths

Slab Edge Considerations

In order to ensure that the SidePlate® connections at the perimeter of a building or adjacent to an opening will fit within the building envelope, the distance from the center line of the column to the edge of slab should be coordinated. As shown in Figure A3, deeper rectangular columns can be shifted “off grid” to fit within the building envelope, when needed. Approximate minimum slab edge (illustrated in Figure A2, variables defined in Figure E2) can be calculated using the equations below (we recommend adding up to a ½ inch of tolerance to these minimum calculations for construction tolerances):

  • When column web is perpendicular to slab edge (Along Grid A in Figure 3)
    • SidePlate® Field Bolted or Welded – ½* dc + tbf + ½”
  • When column web is parallel to slab edge (Along Grid 1 in Figure 3)
    • SidePlate® Field Bolted, Standard – ½* bcf + tbf + 4”
    • SidePlate® SMF Field Bolted, Standard – ½* bcf + 1.35* tbf + 4”
    • SidePlate® SMF Field Welded – ½* bcf + 2* tbf + ½”

dc = depth of column

tbf = thickness of beam flange

bcf = width of column flange

Please contact SidePlate® Systems for project specific dimensions, if needed.

Figure A2 - SidePlate® Field Bolted Standard and Narrow Sections

NOTE: If a minimal slab edge is needed, the narrow bolted configuration (shown in Figure A2) that moves the top set of angles from the outside to the inside face of the side plates may be used. 

Figure A3 - Typical Lateral Column Plan View

Beam Depth Considerations

SidePlate® can accommodate a range of wide flange, HSS, and built-up beam sizes.  Deeper beams generally equate to greater economy, and often the optimal beam depth for SidePlate® is shallower than the optimal beam depth for other moment frame systems. The optimal beam depth will vary from project to project depending on building geometry, criteria, and whether seismic provisions, like SCWB and Span-to-Depth, apply. Figure A2 and A4 show preliminary dimensions for coordination of the side plates.

Figure A4 - SidePlate® Field Bolted Elevation

If you are concerned about issues related to column or beam depth, please contact SidePlate® Systems.


When required by the governing code for certain types of construction, steel SidePlate® connections shall have a fire-resistance rating like that of a "structural frame."

  • The minimum thickness of sprayed on fire-resistive material (SFRM) for steel SidePlate® connection plates, not encased in concrete, shall be determined just like that of a pipe/tube column section with a constant steel wall thickness, which are uniformly heated and protected (the fire exposure of a pipe/tube column is directly analogous to a plate with a 1-sided fire exposure and protection).
  • The SFRM shall have been tested in accordance with ASTM E119 and listed for fire resistive pipe/tube column applications for no less than the required rated time.
  • The contractor shall provide the means for fireproofing across the physical column/beam separation between the bottom beam flange cover plate and the face of the column flange.