Great Opportunity for Polymeric Siding to Show off Performance Advantages for High-Wind Regions
Starting January 1, 2020, all polymeric claddings certified under the VSI program and manufactured after this date will be required to include design pressure labeling on either the product itself or the packaging. Though compulsory in nature, industry stakeholders are thrilled by this development and the Vinyl Siding Institute (VSI) actually led the effort to implement these requirements. Why? Because it will show the “performance-ability” of products in certain high-wind areas, so that code officials and other experts will know that these products will perform in Florida and other coastal places.
The VSI Product Certification Program implemented these new requirements once the relevant ASTM (the American Society for Testing and Materials) standard revisions governing each of the three of the product categories were complete in 2017 - vinyl siding (D3679); polypropylene siding (D7254); and insulated vinyl siding (D7793).
Two Key Components of the Requirements
There are two key components of these revised standards. The first includes the updates to the wind load resistance ratings process and design pressure determination. More specifically, the pressure equalization factor (PEF) for vinyl and insulated vinyl siding increased from 0.36 to 0.50 (while Polypropylene siding’s PEF remained at 0.36). The second requires a specific design pressure rating be determined through testing using ASTM D5206 (the Standard Test Method for Windload Resistance of Rigid Plastic Siding) and included this rating on the product or packaging label.
“It’s a great opportunity for the industry,” says Nick Capezza, VSI’s Director, Technical & Product Certification. “The new requirements help our members communicate their products’ design pressure improvements and other technical aspects more effectively. This will be an essential medium for the polymeric cladding industry to tout superior product performance and ensure the right products are used in coastal areas.”
With vast improvements in design and manufacturing processes, vinyl siding, insulated vinyl siding, and polypropylene siding have become an ideal choice for homes in high-wind coastal areas. While current code standards require siding to withstand wind pressures equivalent to 110 mph on buildings up to 30 feet high, most of the vinyl and polymeric siding can withstand more extreme conditions, making them essential for home building and remodeling in coastal regions.
These unique selling points will appear in the product marketing and technical sales sheets beginning in 2020, along with explicit tips on how to properly install this high-performance siding in high-wind areas. But having the ASTM-standard design pressure rating on a label as required by the VSI Product Certification program enables specifiers and building code officials to determine – without a doubt – which types of products are best suited for high-wind regions. “Polymeric claddings have always been a good performer in high-wind areas,” Capezza asserts. “The required design pressure rating label shows the ability of each particular product to withstand a given amount of wind load. The label gives legitimacy to the advancements made in the products’ performance.”
New Requirements Lead to Expanded Product Labeling
The VSI also feels strongly that the new product labeling will greatly increase consumer confidence in high-wind, hurricane-prone areas, where home and property owners are looking for the right exterior products for their climate. Field research completed in recent years demonstrates the effectiveness of polymeric claddings in high-wind hazard areas, especially during hurricanes, in spite of criticism that the products have “blown off.” A March 2018 technical report published by VSI confirmed that modern polymeric siding products installed properly within the last 20 years performed successfully and as designed during a major storm – including Hurricane Irma in October of 2017. The only exceptions were those that were improperly installed or specified. Thus, the product labeling will emphasize that proper installation and proper product specifications are critical for effective wind resistance.
Another component of the VSI Certification Program is the ASTM’s Standard Test Method for Wind Load Resistance of Rigid Plastic Siding – D5206. Like all building products, vinyl siding, insulated vinyl siding, and polypropylene siding have been tested using ASTM D5206 to gather data on the maximum pressure to which the product is suited. To determine a product’s proper use, its design pressure rating has to be at least as high as the requirements for the location and building. The D5206 procedure, therefore, involves applying incremental air pressure to the product in a test chamber for a specific period of time, analyzing failures at each stage to determine maximum sustained static test pressure, as well as ultimate test pressure. It is intended to simulate the effects of wind loads on exterior building surfaces. Design pressure testing has been in effect for the past 20+ years, but in recent years, testing has distinguished between coastal and non-coastal products with more rigorous standards.
Polymeric siding has improved its resilience in direct relationship with code requirements and standards becoming more stringent. To effectively validate the advancements that they have made in product design and manufacturing processes, the industry created the VSI Product Certification Program in 1996. VSI recently published its Coastal Specification sheet which clearly defines the important aspects of installing product in high wind coastal areas. Stay tuned for more developments on this program leading into the January 1, 2020 kick-off. The industry is excited to share these great product and installation performance improvements, as well as some success stories from Hurricane Irma to best demonstrate these product innovations “in action” during the ultimate test.
