VSI Certification Program Uses ASTM D 3679

by Lee Meyer

Vinyl siding installers used to be notorious for unbelievable claims. Today, thanks to a certification program built around an ASTM standard, the vinyl siding industry can verify the quality of its products for cautious and savvy consumers.

Time was, a call from a siding installation company meant unbelievable claims, performance promises, and other hard-sell techniques designed to rope in homeowners and discredit the competition. A 1987 film, “Tin Men,” even satirized the creative pitches of the aluminum siding salesman in the 1950s.

In today’s marketplace, Internet-savvy, cable television-educated consumers know what to look for in home construction and renovation products, and they aren’t easily swayed by empty claims that can’t be backed up by proven performance. That’s why the Vinyl Siding Institute (VSI), a business unit of The Society of the Plastics Industry, Inc., created the VSI Vinyl Siding Certification Program.

Based on ASTM D 3679, Standard Specification for Rigid Poly(Vinyl Chloride) (PVC) Siding, VSI’s program uses a third-party inspection laboratory to verify that vinyl siding products meet or exceed this quality standard. “The credibility of the ASTM standard, combined with the support of the vinyl siding industry and the objectivity of a third-party administrator, makes the program a reliable resource for vinyl siding that meets basic quality requirements,” said Executive Director Jery Y. Huntley.

Filling a Need

We’ve come a long way since the tin men of the 1950s, both in terms of product quality and marketing sophistication. Over the past few decades, the vinyl siding industry has made myriad technological advances in terms of product consistency, color retention, durability, and profile alternatives. The ASTM D 3679 standard, introduced in 1979, helped solidify the basic quality requirements for the industry.

Knowing that customers demand quality, vinyl siding manufacturers typically say their products meet ASTM D 3679. But until recently, there was no way to verify it. VSI’s members, which make up the bulk of vinyl siding manufacturers in the United States and Canada, recognized the need to create a credible method to validate ASTM D 3679 compliance, legitimize performance standards in the marketplace, assure quality of vinyl siding products, and, ultimately improve product image. In March 1996, VSI’s Steering Committee approved development of a certification program, and by April 1998 had launched the effort, with hundreds of products certified.

Much like ASTM’s consensus-driven process, the VSI Vinyl Siding Certification Program was born of an industry-wide effort, through a certification task force made up of various manufacturer and supplier representatives. The task force researched other programs, developed the framework for the program, addressed technical issues of ASTM D 3679, and created program guidelines. They also selected a third-party administrator for the program, Architectural Testing of York, Pa., and developed a logo/label that could be used to signify certified products.

Quality at Its Core

At the heart of this effort was ASTM D 3679. Built through ASTM’s two-tier balloting process, it has the credibility that consensus standards offer. Better still, since ASTM standards are dynamic products reviewed at least every five years, D 3679 offered the vinyl siding industry the opportunity to improve quality, consistency, and technical accuracy through the certification program and incorporate it into the living standard.

“Using ASTM’s consensus-driven, peer-reviewed format allows VSI’s Technical Committee to develop vinyl siding standards that are more reflective of our customer’s expectations,” said Mark Lavach of Atofina Chemicals, a VSI Technical Committee member. “Our product testing standards are continually reviewed by task groups whose role is not only to improve a standard’s technical content but its readability as well. The end result is a technically valid document that’s suitable for a wide range of users.”

Before the certification program got under way, VSI made sure all aspects of D 3679 were clear to manufacturers, and, in fact, created a Technical Interpretations document to address gray areas. For example, the Technical Interpretations document included a definition for “nominal thickness” until the requirements could be incorporated into ASTM D 3679. The document defined nominal thickness as “the representation for the thickness that the manufacturer consistently uses to describe a given product’s thickness,” e.g., in its product literature. The Technical Interpretations also defined the average thickness and allowable variance from this average thickness, since these items were not explicit in D 3679.

VSI also wants to make it more clear to buyers what it means for a product to meet or exceed ASTM D 3679. Through brochures, fact sheets, and materials created especially for siding salespeople, VSI educates consumers and contractors that when a certified product says it meets the standard, as long as it is installed according to manufacturers’ instructions, it will:

• Meet or exceed the industry standard for quality and performance;
• Withstand the impacts of recommended installation procedures;
• Lay straight on a flat wall;
• Maintain its integrity and not buckle under normal conditions;
• Withstand the effects of normal seasonal temperature fluctuations;
• Stay on the house in heavy winds;
• Maintain a uniform color over time.

“Before we started this program, D 3679 was just another number on a box to customers,” said Amy Lilly. “Now, they know this product has been tested for weatherability, wind load, heat shrinkage, linear expansion, surface distortion, camber, and impact resistance—and we tell them what those tests mean. We’re also verifying that products meet the specifications that manufacturers publicize in their product literature regarding length, width, color, gloss, and of course thickness.”

How the Program Works

Any manufacturer of vinyl siding can apply to certify one or more of its products; each product must be inspected and validated individually. To verify all aspects of ASTM D 3679, the third-party administrator conducts unannounced inspections twice a year in each plant producing certified products, retrieves product as it comes off the line, evaluates plant quality control programs, and conducts tests on the products in its laboratory.

The administrator also reviews product literature and Web sites to validate claims related to ASTM specifications. On thickness, for example, Architectural Testing not only verifies that the product meets the minimum D 3679 standard of 0.035 inches, but measures the product to ensure it is actually the thickness advertised in product bro-chures, within an acceptable margin of error. If a product fails on this or any other test, the administrator works with the manufacturer to correct the quality issue; if the problem is not corrected within the time frame required in the program guidelines, VSI has developed specific guidelines for disqualifying products from the program.

Products that do pass all the inspections are allowed to carry the VSI certification label on their cartons and promote the product using a special logo in their product literature. Use of the logo/label is carefully policed by the program administrator and VSI, to ensure credibility. Certified products are also listed on a special Web site, which is updated frequently as products are added, disqualified, or discontinued.

“Since the program’s inception, nearly every manufacturer that can has certified that one or more of their products meets or exceeds ASTM D 3679,” said Executive Director Jery Y. Huntley. “More than 90 percent of all vinyl siding produced in the United States and Canada is certified through VSI’s program. We feel this has given some real teeth to the ASTM standard.”

Room for Improvement

The “teeth” in VSI’s certification program—unannounced inspections, third-party verification, constant technical clarifications—have made a difference when it comes to marketing vinyl siding to customers as well. “I use certified vinyl siding so that I can meet or exceed my customers’ quality standards,” said George Sponseller, a building contractor in Mt. Pleasant, Mich.

“Certified vinyl siding means quality, control, and confidence,” said Jeff Kester of Regal Wholesale in Falconer, N.Y.

There have been other certification programs for construction products in the past, but not all have garnered the support and consistency that VSI’s Vinyl Siding Certification Program has demonstrated. According to Lilly, having a standard based in ASTM helped tremendously in forming the basis for VSI’s program. “We didn’t have to reinvent the wheel on vinyl siding quality,” she said. “But through ASTM, we keep the door open for constant quality improvement.”

Through VSI’s certification program, ASTM D 3679 and other standards have become more dynamic, being constantly upgraded to ensure consistency. The impact resistance test (ASTM D 4226), for example, is an important part of ASTM D 3679. Over the past several years, the vinyl siding industry has worked on numerous projects aimed at improving the accuracy and repeatability of this test. This work resulted in a series of modifications to the test apparatus and operating procedure that not only improved the accuracy of the test, but reduced its variability by upwards of 30 percent. “The end result is an improved test procedure that gives siding producers and their customers the quality they desire,” said Atofina’s Lavach. “But it doesn’t stop here. We’re still working to make this a better test and ASTM D 3679 a better standard.”

“The vinyl siding industry has put ASTM D 3679 into a broader context with the public by creating this certification program,” said Kathie Morgan, general manager of ASTM’s Technical Committee Support. “And by examining issues involving testing and quality control, VSI members are constantly improving the standard through our ASTM balloting process.”

Beyond the work that VSI is doing to keep ASTM D 3679 a living standard, the organization is working with other trade associations interested in starting quality certification programs. “We’ve learned a lot along the way,” Lilly said. “When it comes to improving product quality, your work is never really finished.” //

Copyright 2002, ASTM