Hide Steel Columns Inside Wall Cavities (Stud Furring)
A steel column can often be concealed within a shallow, nonstructural stud enclosure, but the framing must fit around the column without changing its load path or damaging fireproofing. First verify the column’s full size, required fire protection, access needs, and nearby equipment clearances. Then have the enclosure details checked against local code and the approved structural and fire-resistance designs.
A common mistake is to measure only the visible steel shaft, then frame a tight box around it. Base plates, bolts, welds, cap plates, and fireproofing can extend beyond the shaft. A tight enclosure may damage protection or block inspection, so plan from the full measured envelope, not the column’s nominal size.
Start with the column, not the studs
A column enclosure is a nonstructural finish wall built around a structural steel member. Before choosing stud size or board, confirm what the column supports, how it is protected from fire, and whether the enclosure will affect access, nearby rated construction, or equipment clearances.
I begin by identifying the project jurisdiction and the building and fire code editions it has adopted. Then I review available structural drawings, fire-resistance details, and inspection or maintenance requirements. If records are missing, do not treat the absence of drawings as proof that the column has no special requirements.
Survey the entire column from floor to ceiling. Record its largest projection at the base, shaft, connections, and top. Include fireproofing or other coatings in the measurement, and note nearby pipes, wires, doors, and electrical equipment. The framing needs to clear this actual envelope and allow for installation and any required inspection.
A useful first-pass record includes:
- Column dimensions and the widest point of its base and top connections
- Type and condition of fireproofing or coating, if known
- Floor, ceiling, and wall conditions where the enclosure will meet them
- Nearby utilities, access points, and electrical equipment
- Any engineer, fire-protection designer, or building official who must review the work
There is no universal furring-to-column clearance. The required space depends on the measured conditions, the approved design, and the room needed for construction and inspection. If the enclosure will only fit by pressing against the steel or its protection, pause and ask the structural engineer for direction.
Lay out furring without changing the load path
Stud furring is framing that supports finish material but does not support the building. Its job is to create a straight surface around the column, not to brace, straighten, or carry loads from the steel member.
Set out the enclosure on the floor and ceiling from the column’s widest measured projection. Allow enough space to build the frame without scraping or compressing fireproofing. The exact offset is project-specific; do not copy a generic detail when plates, bolts, or coatings differ.
Use a framing layout suited to the enclosure and its finish. Keep the new work stable through its approved connections to surrounding construction, rather than relying on the steel column as an attachment point. Have the structural engineer approve any proposed attachment to the column or any change to its coating, fireproofing, connections, or adjacent construction.
Do not cut, drill, weld to, notch, or load the column without written approval from the responsible engineer and any required authority. Do not remove or compress fireproofing to make the framing fit. These are not finish adjustments; they can affect the structure or its approved fire protection.
Check electrical working space before closing the layout
Electrical working space is the clear area required in front of certain electrical equipment so it can be operated and serviced safely. It is not a general clearance rule for steel columns, and a column enclosure must not reduce it.
Where electrical equipment is present, check the adopted electrical code and the equipment conditions. Under the 2023 National Electrical Code, Section 110.26(A)(1), working-space depth depends on voltage and conditions. Width must be at least 30 inches or the equipment width, whichever is greater, and headroom must be at least 6 feet 6 inches.
These dimensions do not give permission to place an enclosure in every location that appears to meet them. Confirm the applicable table conditions, equipment location, and local adoption with the electrical designer or authority. If the proposed wall makes the required space smaller, revise the layout rather than shrinking the clearance.
Preserve fire protection and required access
Fireproofing is material or a tested system intended to protect steel from heat in a fire. It is not spare space that can be removed, covered without review, or used as a convenient surface for fastening studs.
The column’s required protection comes from the approved design and applicable code. If it is damaged, discontinuous, undocumented, or incompatible with the planned enclosure, stop and consult the fire-protection designer or engineer. A layer of ordinary gypsum board does not, by itself, prove that the column or enclosure has a fire-resistance rating.
Where a rated enclosure is required, use a compatible, approved fire-resistance design. Match its specified materials, number of layers, fasteners, joints, and installation details. Relevant test standards include ASTM E119 and UL 263, but naming a test standard is not a substitute for an applicable listed or approved assembly.
Concealed vertical spaces may require fireblocking under the locally adopted code. For example, the 2021 IRC R302.11 and 2021 IBC 718.2.2 address fireblocking in applicable concealed spaces at floor and ceiling levels and at 10-foot intervals. Confirm which provisions apply to this project before covering the framing.
Do not seal an inspection point or service access that must remain available. Mark required access locations on the framing plan, and decide how the finish will open or be removed without damaging the rated assembly. Any access detail in a rated enclosure must also comply with the approved design.
Choose a finish that fits the enclosure
The finish should follow the fire and access requirements, not set them. Board type and thickness, joints, and fastening pattern must match the approved design wherever a rating is required. For a nonrated enclosure, still confirm that the chosen finish suits the room and can be installed without contacting the steel or its coating.
| Project condition | Planning response | Do not do |
|---|---|---|
| Column has a wide base plate or exposed bolts | Measure the widest projection and lay out framing beyond it | Size the wall from the shaft alone |
| Existing fireproofing is damaged or unknown | Pause for review by the responsible designer or engineer | Cover it and assume the finish restores protection |
| Electrical equipment is nearby | Verify NEC working space for the equipment and adopted code | Treat column clearance as a substitute for working space |
| Enclosure is part of a rated assembly | Follow an applicable approved or listed assembly in full | Claim a rating from ordinary gypsum board alone |
| Concealed space falls under fireblocking rules | Detail required blocking before board installation | Close the cavity and leave the issue for later |
| Steel is near an exterior thermal boundary | Review moisture and condensation risk as part of the envelope design | Enclose the steel before resolving the wall condition |
A closed column cavity does not have a universal airflow or CFM requirement. Do not connect it to HVAC or block a ventilation path that is required by the building design. If the column sits near an exterior thermal boundary, resolve the envelope and condensation risk before concealment.
Build, inspect, and document in sequence
A reliable installation is planned in stages. This makes it easier to catch clearance, fire-protection, and access problems before they disappear behind finish material.
Confirm the design basis. Identify the local code editions, the column’s structural role, its fire-protection requirements, and any required inspections. Ask the responsible professionals to resolve missing or conflicting information.
Measure the full envelope. Record the shaft, plates, bolts, welds, and protection. Transfer the largest projection to the floor and ceiling, then check the proposed wall against doors, utilities, and equipment working space.
Get attachment and fire details approved. Keep furring non-load-bearing. Obtain the engineer’s approval for any attachment to the column or change to its protection. Confirm the required rated assembly and fireblocking before framing is closed.
Frame and check the cavity. Build around the measured envelope without scraping, compressing, or covering required fireproofing in an unapproved way. Keep inspection and service points usable. Do not add an assumed ventilation opening or connect the cavity to HVAC.
Record the work before board goes on. Photograph the column, connections, fireproofing, clearances, fireblocking, and access provisions. Obtain required structural or fire inspections before concealment.
Verify the finished enclosure. Confirm that the installed materials and details match the approved design. Check that electrical working space, inspection points, and service access remain clear.
Two planning scenarios
These examples are illustrative planning scenarios, not reports of specific completed projects. They show how the same furring approach changes when the column’s details and surroundings differ.
Column with a projecting base plate
A designer wants a clean, square enclosure around a column in an open living area. The shaft appears narrow, but the base plate and bolts extend farther out. I would set the layout from that wider projection, then check how the resulting enclosure meets the floor and nearby circulation space.
If the plate cannot fit without the frame touching fireproofing or steel, the answer is not to trim the protection or attach the frame to the column. The engineer must review the constraint and guide a revised detail.
Column beside electrical equipment
A renovation places a new wall near a column that also sits beside electrical equipment. The first task is to check the equipment’s required working-space depth, width, and headroom under the applicable code conditions. Those clearances may control the wall position more than the column itself.
If the enclosure would reduce required space, move or redesign the enclosure with the project team. Do not count a narrow gap between the furring and column as electrical working space unless it actually meets the equipment rules.
Frequently asked questions
These answers address common planning questions for concealing a steel column with stud furring. Final requirements depend on the adopted codes, approved structural and fire-resistance designs, and site conditions.
Can I attach metal studs directly to a steel column?
Do not assume that direct attachment is acceptable. Have the structural engineer approve any attachment, since drilling, welding, or other changes may affect the member or its protection. A nonstructural enclosure should not brace or carry loads from the column.
How much space should I leave between the steel and furring?
There is no universal clearance. Measure the full column envelope, including plates, bolts, welds, and fireproofing, then allow for installation and required inspection. Ask the engineer for direction if the framing cannot fit without contact or damage.
Can I cover existing fireproofing with drywall?
Only when the proposed assembly is compatible with the approved fire-resistance design and local requirements. Do not assume ordinary drywall restores, replaces, or maintains a rating. Get professional review if the protection is damaged, undocumented, or in conflict with the enclosure.
Does every column enclosure need fireblocking?
Not in every case. Fireblocking applies where the adopted code requires it for the concealed space. The 2021 IRC and IBC include provisions for applicable concealed vertical spaces, including floor and ceiling levels and 10-foot intervals. Verify the governing code and project conditions.
Does the cavity need ventilation?
There is no universal CFM requirement for an ordinary, non-ducted column enclosure. Do not connect it to HVAC or block an existing required ventilation path. If the steel is near an exterior thermal boundary, review moisture and condensation risk before closing the wall.
Can the enclosure reduce electrical working space?
No. Where electrical equipment is present, preserve the working space required by the adopted electrical code. NEC 2023 Section 110.26(A)(1) sets depth by voltage and conditions, with a width minimum of 30 inches or equipment width, whichever is greater, and 6 feet 6 inches of headroom.
Will gypsum board alone give the column a fire rating?
Do not claim a rating from gypsum board alone. Where a rating is required, use an approved or listed design and follow its specified materials, layers, fasteners, and joints. ASTM E119 and UL 263 are relevant test standards, not stand-alone installation instructions.
What should I photograph before closing the wall?
Record the column and connections, fireproofing condition, framing clearances, fireblocking, and any required access. Keep the photos with project records and arrange required inspections before installing finish board. This creates a useful record of work that will soon be concealed.
(This article was written by one of our staff writers, Michael Donovan. Visit our Meet the Team page.)
