STEEL STUD SPACING STANDARDS FOR COMMERCIAL WALLS: A CODE-BASED GUIDE
Detailed breakdown of stud spacing requirements under the National Building Code of Canada and Alberta Building Code for various wall types and heights.
Stud spacing is one of the most consequential decisions in commercial steel stud framing design. The selected spacing affects the structural performance of the wall, its fire resistance rating, its acoustic performance, and the cost of both materials and labour. This guide examines the code-based requirements for stud spacing in commercial construction in Alberta, with practical guidance for common wall types and heights encountered in Edmonton commercial projects.
THE GOVERNING STANDARD: ASTM C754
ASTM C754, Standard Specification for Installation of Steel Framing Members to Receive Screw-Attached Gypsum Panel Products, is the primary standard governing steel stud installation in North America. It specifies maximum stud spacings based on stud width, gauge, and wall height, and is referenced by both the National Building Code of Canada and the Alberta Building Code.
DEFLECTION CRITERIA
The Alberta Building Code requires that non-structural partition walls be designed to resist a minimum lateral load of 0.25 kPa (5 psf) with a maximum deflection of L/240 under this load. For walls in high-traffic areas or areas with special requirements, a more stringent deflection limit of L/360 or L/480 may be specified by the structural engineer of record.
The deflection limit is the primary driver of stud spacing selection for taller walls. As wall height increases, the required stud gauge and/or spacing must be adjusted to maintain compliance with the deflection limit. For walls over 14 feet in height, an engineer of record must specify the framing system.
STANDARD SPACING APPLICATIONS
24" O.C. (610mm): The most common spacing for standard interior partitions in commercial buildings. Suitable for walls up to approximately 12 feet in height using 20-gauge 3-5/8" studs, or up to 10 feet using 25-gauge studs. This spacing minimizes material cost and is the most efficient for labour.
16" O.C. (406mm): Required for taller walls, walls subject to higher lateral loads, or walls that must meet more stringent deflection criteria. Also required for some fire-rated assembly designs. Increases material cost by approximately 50% compared to 24" o.c. spacing.
12" O.C. (305mm): Used for very tall walls, walls subject to significant lateral loads, or specialized applications such as shaft walls. Rarely used for standard interior partitions.
FIRE-RATED ASSEMBLY REQUIREMENTS
Fire-rated wall assemblies have specific stud spacing requirements as part of the UL-listed design. For example, UL Design U305 (a common 1-hour fire-rated partition) requires 3-5/8" 25-gauge studs at 24" o.c. with specific drywall types and fastening patterns. Deviating from the listed spacing voids the fire rating. Always verify the stud spacing requirement in the applicable UL design before beginning installation.
GoldStar Builders Corporation installs steel stud framing systems in strict compliance with ASTM C754 and UL-listed assembly requirements on commercial projects throughout Edmonton. Visit goldstarbuilders.ca for more information.