Stiffening panels is necessary for most metal wall panel projects, especially those with larger panels.* It is essential for two main reasons: panel longevity and aesthetic appeal to minimize perceived waviness, commonly called “oil canning.” Credible manufacturers will stiffen metal wall panels by attaching an extruded profile to the back of a panel by means of adhesives or tapes, and space them properly to meet the wind load criteria performance requirement.
It is evident in today’s metal wall panel market that there are manufacturers and installers not complying with performance requirements called out in the building specifications. They use little to no stiffeners on panels to cut costs and potentially save themselves manufacturing time. Why? It’s simple, they do not want to go through the expense of proper testing. There is a cost to stiffening panels properly. Corners are cut in an effort to close a project instead of taking the high road and doing it correctly.
On the flip side, many credible manufacturers have designed and tested their own systems to provide customers with a proven product. Testing systems is best done with reputable engineering and third party testing companies. Although it adds expense, the product will perform as specified and be aesthetically pleasing.
*Smaller size panels may not require stiffeners at all and should perform properly and allow the panel to deflect per those requirements.
What does this mean to architects, general contractors, and building owners?
Partner with educated manufacturers. Insist on seeing their testing data. Although we’ve focused on stiffening metal wall panels in this article, architects and specifiers should insist on all types of testing for the panel systems considered for the project.
It is always best to inquire with the more reputable manufacturers. They can support each wall panel system with testing data and help guide you through the process with a well-educated design team. This ensures you get a high performing product that meets the aesthetic requirements you desire. Depending on the type of panel system–whether a caulked wet joint or a dry joint system–it is crucial to consider other testing that should be included and expected.
How are you assured that you are getting what you are paying for?
Typically, the more reputable metal wall panel manufacturers will meet the industry standard 30 PSF wind load with L/60 deflection criteria and insure the engineering for stiffening the panels with test data. The height and/or the location of the building must be considered in conjunction with the industry standard as it may dictate a higher wind load performance.
In most high rise structures, the buildings should be supported with wind load data for the entire structure to insure that this information is being included in the wall panel package with supporting engineering data. Alternatively, most low rise buildings are not supported with this type of data.
Lastly, it should be a requirement for all manufacturers to support the panel system with other testing data relative to the system being utilized to include the following:
- Structural Performance/Uniform Load Deflection Test: Provide a panel system that has been tested in accordance with ASTM E330, specify wind load criteria expected on structure
- Engineering calculations, stamped with sealed documents.
Other panel tests to take into consideration
Standard tests for barrier wall systems or wet joint systems:
- Air Infiltration E283 Static
- Water Penetration E331
Standard tests for dry joint systems:
- AAMA 509-09 for Back Ventilated Rain Screen Systems
- AAMA 508-07 for Pressure Equalized Rain Screen Systems
For more information about wind load performances or any other questions about products we offer, feel free to give us a call at 1-866-260-4047 or email info@www.www.americlad.com
