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CAN CSA O122-16: Structural Glued-Laminated Timber — Requirements and Compliance
Comprehensive Overview of the Canadian Standard for Manufacture, Quality Control, and Certification of Glulam
CAN CSA O122-16 is the 2016 edition of the Canadian national standard for structural glued-laminated timber (commonly referred to as glulam). Developed by the Canadian Standards Association (CSA) under the category of wood products, this standard defines comprehensive requirements for the manufacture, testing, quality control, and certification of glulam members used in building and construction. It serves as the primary benchmark for ensuring the structural reliability, durability, and safety of engineered glued-laminated timber products in Canada, and is frequently referenced by the National Building Code of Canada (NBCC) and provincial regulations.
Scope of CAN CSA O122-16
The standard applies to all structural glued-laminated timber members manufactured with adhesives, including straight and curved members, as well as members designed for horizontal (beam) or vertical (column, arch) applications. The scope covers:
- Raw materials — lumber species and grades, adhesives, and end-joint materials.
- Manufacturing processes — laminating, finger-joining, curing, and finishing.
- Performance criteria — strength, stiffness, durability, and dimensional stability.
- Testing and inspection — quality control tests during production and final acceptance.
- Marking and certification — product labeling and third-party certification requirements.
CSA O122-16 does not apply to non-structural laminated timbers nor to members fabricated with mechanical fasteners alone. It is intended for use by glulam manufacturers, engineers, specifiers, and building officials.
Tip: When specifying glulam in Canada, always reference the current edition of CAN CSA O122-16 together with the relevant NBCC load and resistance factor design (LRFD) requirements.
Technical Requirements
CAN CSA O122-16 sets out detailed technical requirements to ensure consistent performance of glulam products. The key areas are outlined below.
Lumber and Adhesive Specifications
- Lumber grades: Only lumber meeting CSA O141 or equivalent grading rules is permitted, with limits on knots, slope of grain, and other strength-reducing characteristics.
- Moisture content: Lumber at the time of gluing must have a moisture content between 9% and 15%, with a maximum difference of 5% between adjacent laminations.
- Adhesives: Must meet durability requirements for intended service conditions (dry, wet, or protected). Adhesives must conform to CSA O112 (phenolic, resorcinol, or polyurethane types) and be capable of producing a bond that passes prescribed delamination and shear tests.
Finger Joints and End Joints
All end joints in glulam must be finger joints conforming to CSA O122 configuration requirements. Joints must be tested for tensile strength according to the standard’s sampling plan, with minimum strength requirements based on the grade of lumber used.
Layup and Performance Requirements
The standard defines a system of combination symbols (e.g., 20f-ES, 24f-EC) that relate to bending strength class, visual appearance grade, and end-use. Each combination symbol has associated allowable design values for bending, tension, compression, shear, and modulus of elasticity. The table below summarizes typical test requirements for glulam quality control.
| Test Parameter | Frequency | Acceptance Criteria (Per CSA O122-16) |
|---|---|---|
| Delamination (cyclic wet/dry) | 1 per production shift or per 20 m³ of product | Maximum total delamination ≤ 5% of bond-line length; no individual delamination > 25% of bond line |
| Block shear (dry and wet) | 1 per 200 laminations or per shift | Average wood failure ≥ 80%; minimum individual wood failure ≥ 60% |
| Tension proof test of finger joints | 1 per 500 joints or per shift | Minimum tensile strength ≥ 60% of the design value for the lumber grade |
| Moisture content check | Every lamination at time of gluing | 9% – 15% and within 5% between adjacent laminations |
Warning: The test frequencies and acceptance criteria presented are examples. The latest edition of CAN CSA O122-16 should always be consulted for the complete set of requirements, which may differ according to the manufacturer’s quality control plan.
Implementation in Quality Assurance Programs
Compliance with CSA O122-16 is verified through a two-tier system: the manufacturer’s own quality control (QC) program and third-party certification by an accredited inspection agency (e.g., APA, Timber Products Inspection, or others recognized by Standards Council of Canada).
Factory Production Control
Manufacturers must document and implement a QC plan covering incoming material inspection, in-process checks, and final product testing. Records must be retained for at least 5 years. Retesting protocols and traceability are mandatory.
Certification and Marking
Each glulam member that meets the requirements must be marked with a certification mark (e.g., CSA O122 / NBCC / XXX). The mark includes the combination symbol, manufacturer identifier, and the standard reference. Uncertified material cannot be labeled as conforming to CSA O122.
Success: Many building codes in Canada now require glulam used in primary structural frames to carry a CSA O122 third-party certification mark. Specifying certified glulam simplifies acceptance by building officials and reduces liability.
Compliance and Certification Notes
Engineers, architects, and contractors should be aware that CSA O122-16 was published in 2016 and is currently under systematic review; a reaffirmation or update may be released in the 2026 cycle. It is essential to use the most current version referenced by the applicable building code.
Key compliance points:
- All glulam for structural use in Canada must comply with CSA O122 unless an alternate standard is specifically permitted by the authority having jurisdiction.
- Design values for glulam are derived using procedures in ASTM D3737 and are included in the standard for each combination symbol.
- Standard CSA O122-16 harmonizes with key U.S. glulam standards (ANSI A190.1) but differs in some test methods and lumber grading requirements.
Q: What is the difference between CSA O122-16 and ANSI A190.1?
A: While both standards cover structural glulam, CSA O122-16 uses Canadian lumber grades (CSA O141) and includes combination symbols specific to Canadian practice. ANSI A190.1 relies on U.S. lumber rules and produces slightly different design values for similar sizes and load conditions.
A: While both standards cover structural glulam, CSA O122-16 uses Canadian lumber grades (CSA O141) and includes combination symbols specific to Canadian practice. ANSI A190.1 relies on U.S. lumber rules and produces slightly different design values for similar sizes and load conditions.
Q: Does CSA O122-16 apply to glulam used in outdoor or wet service conditions?
A: Yes. The standard defines three service categories: dry (DRY), wet (WET), and protected (PRO). Each requires a different adhesive durability rating and may impose more restrictive moisture content limits. The appropriate service category must be specified at the time of design and ordering.
A: Yes. The standard defines three service categories: dry (DRY), wet (WET), and protected (PRO). Each requires a different adhesive durability rating and may impose more restrictive moisture content limits. The appropriate service category must be specified at the time of design and ordering.
Q: How often must a glulam manufacturer requalify under CSA O122-16?
A: Third-party certification typically requires annual audits and continuous testing as per the manufacturer’s QC plan. If there is a change in adhesive, lumber species, or production process, additional qualification testing may be required before production resumes.
A: Third-party certification typically requires annual audits and continuous testing as per the manufacturer’s QC plan. If there is a change in adhesive, lumber species, or production process, additional qualification testing may be required before production resumes.
Published: 2016 | Review Cycle: 2026. This article provides general guidance and does not replace the official CAN CSA O122-16 standard.