Understanding CSA Tested Roofing Assemblies with Elevate Canada’s Technical Services & Training Manager
When it comes to designing safe, durable roofing systems in Canada, tested performance is more than a recommendation–it’s a requirement.
We spoke with Yogesh Bhowany, Technical Services & Training Manager at Elevate Canada, who brings over 12 years of roofing industry experience, to get his perspective on the importance of CSA-tested assemblies. Yogesh shared his expertise on the testing process, critical considerations, available tools, and the range of Elevate CSA-tested assemblies.
Why CSA Tested Assemblies Matter
The National Building Code of Canada (NBCC), outlines strict wind load provisions for roof system design. Meeting these provisions means understanding and applying the CSA A123.21 Standard test method for the dynamic wind uplift resistance of membrane-roofing systems, a key element in ensuring roof assemblies meet or exceed performance expectations.¹
Under the NBCC, every roof must be designed to withstand specific wind loads based on parameters such as building location, height, openings, risk category and exposure. To comply, roofing systems need to be tested according to the CSA A123.21test standard, which evaluates their resistance to dynamic wind uplift pressures.
The CSA A123.21 standard was first published in 2004 and has since undergone revisions in 2010, 2014, and most recently in 2020 to reflect advancements in testing methods and building science. Research and development for the standard is led by the National Research Council of Canada (NRCC)’s consortium-based research and development study group “Special Interest Group for Dynamic Evaluation of Roofing Systems (SIGDERS).”
The Process
Determining the Wind Load Requirements
Article 4.1.7.1 of the NBCC 2020 provides the process to calculate the wind load requirements for every project. For architects, consultants, engineers, and specifiers, proper wind load calculation is critical. The NBCC places responsibility for determining wind load requirements on the design authority, meaning that every project must begin with accurate data.
The National Research Council of Canada offers the Wind-Roof Calculators on the Internet (Wind-RCI), a free online tool to assist in determining wind load requirements for specific project conditions.
Testing to CSA A123.21 for Wind Uplift Resistance of Roofing Systems
Section 5.2.2.2 of the NBCC 2020 specifies that the wind uplift resistance of the membrane roofing systems shall be determined in accordance to the requirement of CSA A123.21
The CSA A123.21, Standard test method for the dynamic wind uplift resistance of membrane-roofing systems is the test standard for membrane roofing assemblies. When the tested roof assembly is subjected to the CSA A123.21 testing procedure, the test specimen will obtain a sustained pressure that it has passed. A sustained pressure of 240psf or less is multiplied by a resistance factor of 0.65 to obtain the factored wind uplift resistance of the tested roof assembly.
Selecting the compliant Roofing System
To comply with the NBCC requirements for each project, the roof assembly selected must have a higher wind uplift resistance than the wind load requirements calculated for the field, perimeter and corner zones.
Elevate Tested Roofing Assemblies
At Elevate, we understand the importance of providing tested assemblies that meet Canada’s demanding codes. Our portfolio of roofing solutions includes a wide range of systems tested under CSA A123.21, ensuring specifiers have options that balance performance, design flexibility, and installation efficiency.²
Whether the project calls for Mechanically Fastened, Fully Adhered, or Hot/Cool Applied attachment methods, Elevate offers tested assemblies for EPDM, TPO, PVC, and SBS roofing systems. For each roofing system type, Elevate provides dedicated tested assembly guides to help you quickly identify code-approved assemblies, ensure compliance with project requirements, and streamline system selection with confidence.
RubberGard EPDM Tested Assembly Guide
UltraPly TPO Tested Assembly Guide
Elevate PVC and MAX PVC Tested Assembly Guide
Elevate Asphalt Tested Assembly Guide
Important Factors to Consider
Section 5.2.2.2 (4) of the NBCC confirms that the CSA A123.21 applies only to membrane roofing systems whose components’ resistance to wind uplift is achieved by fasteners or adhesives. It does not apply to roofing systems that use ballast, such as gravel or pavers, to secure the membrane against wind uplift.
Staying Informed
Building codes and testing standards evolve alongside advancements in technology and materials, and staying up to date is essential. The upcoming new edition of the CSA A123.21 standard will bring about a few major revisions.The NRC, along with roofing associations such as CRCA (Canadian Roofing Contractors Association), RCABC (Roofing Contractors Association of British Columbia), and CSC (Construction Specifications Canada), regularly share updates through various communication channels such as magazines and E-newsletters.
By staying informed and working with manufacturers who prioritize tested, code-compliant solutions, industry professionals can ensure every project meets the highest standards of safety and performance.³
If you have questions related to an upcoming project or would like to discuss codes and testing in more detail, please contact your local Elevate sales representative for more information.
1 References to the National Building Code of Canada (NBCC) and CSA A123.21 are provided for informational purposes. Compliance with applicable building codes, standards, and local regulations remains the responsibility of the project design authority and installer. Always confirm requirements with the local authority having jurisdiction.
2 CSA-tested results reflect laboratory conditions. Test outcomes do not replace the need for site-specific engineering or design review. Only tested assemblies listed in current Elevate assembly guides are eligible for compliance review.
3 Actual project performance may vary depending on design, installation, environmental conditions, and maintenance. The information provided is for general guidance only and should not be construed as a guarantee of performance under all conditions.