For a typical non-load-bearing interior partition, start with the wall height, required wall depth, stud spacing, board assembly, and loads from doors, cabinets, fixtures, or finishes. Common nominal depths include 2-1/2 inches, 3-5/8 inches, and 6 inches, but there is no universal stud size or maximum height. Ontario’s applicable table and the manufacturer’s design data must match the exact wall conditions.
Start with the wall’s job, not the stud size
An ordinary drywall partition usually starts with a light-gauge, non-load-bearing steel stud system. That changes if the wall supports building loads, reaches an unusual height, carries concentrated loads, or forms part of a fire-rated, acoustic, exterior, or engineered assembly.
For non-load-bearing interior walls, Ontario’s 2024 Building Code tables connect stud size and maximum spacing to wall height and the selected assembly. They do not establish one steel-stud size for every partition. The code came into effect on January 1, 2025. Review the Ontario SB-3 fire and sound resistance tables alongside the project drawings and current manufacturer data.
Confirm whether the wall is non-load-bearing
Use non-load-bearing interior studs when the partition carries its own wall finish and compatible attachments, but does not support floors, roofs, beams, exterior cladding, or other structural loads. A partition can still require careful design if it is tall, heavily finished, exposed to lateral pressure, or fitted with concentrated loads.
Load-bearing studs, exterior structural framing, curtain-wall members, floor framing, ceiling framing, and house framing are different applications. They require the relevant structural properties, connections, bracing, load combinations, and project design. A light-gauge drywall stud is not a substitute for a load-bearing member.
Steel studs versus wood studs
Neither material is automatically right for every interior partition. The decision depends on the specified assembly, height, fire and acoustic requirements, available depth, attachment details, services, schedule, and applicable design information. A generic article cannot select one material for every wall.
Steel can be used in house-framing systems, but house framing is not the same as choosing drywall studs for an interior partition. Exterior exposure, gravity loads, wind, floor and roof connections, thermal detailing, bracing, corrosion conditions, and engineering become part of that decision.
What steel-stud size and gauge actually mean
A steel-stud designation contains several separate measurements. “Size” may refer to nominal depth, while gauge or thickness describes the steel itself. Read the complete manufacturer designation before ordering.
- Nominal depth: the approximate distance from the stud web to the front edge of the flanges. Common interior choices include 2-1/2, 3-5/8, and 6 inches.
- Web: the central portion of the C-shaped stud that largely determines the wall cavity.
- Flange: the side leg that receives board fasteners and contributes to the profile.
- Return lip: the folded edge of the flange that affects profile, stiffness, handling, and fastening.
- Length: the supplied member length for the floor-to-ceiling condition and selected head and sill details.
- Gauge or actual thickness: the steel thickness category stated in product data. Gauge numbers are not interchangeable across every standard.
20 gauge steel is thicker than 25 gauge steel. A thicker member generally improves resistance to local damage, stiffness, and fastener performance, but it does not create a universal allowable height or load rating. Spacing, geometry, bracing, board attachment, loading, and the design table still control.
Compare 2-1/2-inch, 3-5/8-inch, and 6-inch studs
Nominal depth is primarily a wall-cavity decision. It affects finished wall thickness, room for insulation and services, and available framing options, but it does not establish structural capacity, fire performance, sound performance, or code compliance by itself.
| Nominal depth | Useful starting point | Advantages | Tradeoffs |
|---|---|---|---|
| 2-1/2 inches | Compact partitions | Uses less floor area and suits small service runs | Less room for wiring, plumbing, insulation, backing, and reinforcement |
| 3-5/8 inches | Common interior partition starting point | Balances wall depth, service space, board support, and component compatibility | Not universal for every height, spacing, finish, or load |
| 6 inches | Taller, deeper, more serviced, or more insulated partitions | Provides greater cavity space | Consumes more floor area and may require different detailing |
Choose a deeper profile when plumbing, insulation, backing, or the specified assembly needs more cavity space. Do not choose 6-inch studs solely because a wall “feels stronger”; verify member, thickness, spacing, and design assumptions together.
Spacing and thickness: the two choices that change the wall
Metal studs are commonly laid out at 12, 16, or 24 inches on centre. The correct spacing depends on stud properties, board installation, height, loads, and the applicable table or design.
- 12 inches on centre: closer support for demanding board, finish, height, or loading conditions, with more material and installation time.
- 16 inches on centre: a common interior layout that often balances board support and material use.
- 24 inches on centre: fewer studs, but greater unsupported board span and potentially different height, finish, backing, and chart requirements.
Closer spacing does not automatically make an unsuitable stud acceptable. Thicker steel can change stiffness, screw engagement, local resistance, and handling, but thickness or gauge must be selected as part of the complete wall design.
Project conditions that control the selection
Use these rules as a screening process, then verify the result against the applicable technical table.
Taller walls
Start with actual floor-to-ceiling height and unsupported stud height. A tall partition may need a different depth, thicker steel, closer spacing, additional bracing, a different board assembly, or structural design.
Doors, cabinets, and fixtures
Door jambs, closers, wall cabinets, shelving, sinks, handrails, televisions, and heavy equipment can require reinforced jambs, backing, additional studs, stronger connections, or heavier framing.
Multiple board layers and heavy finishes
Additional gypsum layers, tile, stone, resilient channels, panels, and other finishes affect wall mass and attachment requirements. A tested fire or acoustic assembly must be followed as a complete system.
Wiring and plumbing
Interior steel-stud walls can accommodate planned services through suitable openings, subject to stud geometry, protective requirements, and limits on cutting or altering members. A crowded cavity may justify a deeper stud, furring arrangement, or separate chase.
Fire, acoustic, and movement requirements
Use the specified assembly and its listed components. Performance depends on studs, track, board, insulation, sealants, fasteners, joints, and detailing together.
How to read a steel-stud height or span chart
There is no single safe answer to the maximum height of 3-5/8-inch metal studs. The result changes with the exact stud series, thickness, spacing, lateral load, allowable deflection, board layers, bracing, support condition, and application.
- Identify the application: confirm the chart covers non-load-bearing interior partitions.
- Match the member: check depth, flange, return lip, thickness or gauge, and product series.
- Match spacing: use the row for 12, 16, or 24 inches on centre.
- Confirm height or span: check whether the measurement is clear height, stud length, or unsupported span.
- Read lateral-load assumptions: do not transfer a value calculated for one pressure to another condition.
- Check deflection: a stricter limit can reduce permitted height.
- Match board conditions: verify layer count, thickness, sides, bracing, and sheathing assumptions.
- Review notes: check openings, concentrated loads, fasteners, track, deflection details, and engineering requirements.
Use the lowest value that matches all project conditions, not the most favourable value on the page. If an assumption differs, the chart is not a reliable ordering basis.
Four hypothetical wall selections
These examples are hypothetical and show how the decision changes without assigning capacity or product availability to a particular product.
Standard room partition
A normal-height, non-load-bearing partition with gypsum board on both sides and no heavy equipment may use a 3-5/8-inch light-gauge system as a starting point. Confirm height, board assembly, spacing, and the manufacturer’s table first.
Taller partition
A commercial wall well above typical room height cannot be selected from the 3-5/8-inch label alone. Compare the exact member and thickness at the required spacing, then consider deeper or heavier framing, closer spacing, or bracing if the chart does not support the condition.
Wall with cabinets and a door opening
The field of the wall may use one partition member, while jambs, headers, cabinet backing, fasteners, and connections require separate coordination. Identify concentrated loads before ordering.
Wall with significant service space
A washroom or mechanical-adjacent partition with pipes, valves, electrical runs, and insulation may outgrow a 2-1/2-inch cavity. Consider a deeper profile, coordinated chase, or separate service zone.
Coordinate the stud with the complete wall system
Studs should be selected with track and connection details. Match nominal depth, flange geometry, thickness, and connection method between stud and track.
- Coordinate bottom-track substrate, fasteners, alignment, and moisture conditions.
- Use standard or deflection head-of-wall track according to the movement detail.
- Plan door jambs, headers, access panels, corners, intersections, and board backing.
- Locate flat strips, reinforcement, clips, or additional framing for cabinets and equipment.
- Route services through intended openings where possible and protect them from fasteners and sharp edges.
- Include specified bridging, channels, clips, or bracing.
A stud count alone will not produce a buildable order if the project needs jamb members, headers, deflection track, backing, clips, bridging, or special profiles.
When the table is not enough
Ask for manufacturer technical review or project-specific design input when the wall is structural, unusually tall, exposed to significant lateral loads, heavily loaded at isolated points, part of a fire-rated or acoustically tested assembly, or shaped around unusual openings. The same applies to nonstandard profiles or charts that do not match project assumptions.
Use the applicable product data, load tables, standards, and safety documentation for the exact member and project condition. Do not substitute a general document for the technical information that governs the selected wall assembly.
Information to include in a quote or submittal request
- Project name, location, wall identification, and intended application.
- Confirmation that the wall is non-load-bearing, or structural design information.
- Finished and clear stud height.
- Required depth, service-cavity needs, thickness or gauge, spacing, geometry, and length.
- Board layers, insulation, tile, panels, and other finishes.
- Doors, cabinets, shelving, handrails, equipment, backing, and concentrated loads.
- Bottom track, head-of-wall track, movement requirements, and connections.
- Corners, intersections, openings, jambs, headers, penetrations, bridging, clips, and accessories.
- Required technical documents and submittal format.
- Quantities, cut lengths, packaging, delivery sequence, and receiving constraints.
Provide these details to the framing supplier or design team so the framing category can be evaluated without guessing at dimensions, capacity, price, or availability.
Frequently asked questions
What is the maximum height for 3-5/8-inch metal studs?
There is no universal maximum. Confirm exact thickness and profile, spacing, lateral load, deflection, board layers, bracing, supports, openings, and the applicable design table.
How far apart should metal studs be in an interior wall?
Common layouts are 12, 16, or 24 inches on centre. Select the spacing that matches the stud, board assembly, height, loads, and project requirements.
Which is thicker, 20 or 25 gauge metal studs?
20 gauge steel is thicker than 25 gauge steel. Gauge alone does not establish permitted height or load capacity.
Can steel studs be used to frame a house?
Yes, but house framing is a different design task from selecting non-load-bearing interior drywall studs. It must address gravity, wind, connections, bracing, exterior exposure, thermal performance, and structural design.
Can wiring and plumbing pass through interior steel studs?
Yes, if the layout, openings, protection, fastening, and member limitations are coordinated. Use a deeper cavity or separate service zone when services cannot fit without crowding or damaging the framing.
Turn the sizing decision into a verified order
Before ordering, record wall height, depth, thickness or gauge, spacing, board assembly, concentrated loads, track and deflection requirements, openings, services, quantity, and required documents. To review the relevant interior framing product category, see non-load-bearing light-gauge steel studs.
