Metal Building Article: Industry Faces Uncertainty over Perimeter Joint Testing

Code debate continues, decisions expected in coming months

By Jennifer G. Prokopy

No code issue in recent history has been more hotly debated than the issue of perimeter joint testing. Manufacturers, engineers, building officials, independent consultants - everyone has an opinion, and not many can find room to agree. At issue is the development and promulgation of a new testing method to be adopted into the International Building Code. It's one that some argue is unnecessary, and others believe is essential to safe construction. Still others seek a happy medium: a new test with allowances for a variety of applications.

This complicated issue has potentially far- reaching implications. As a result, many industry organizations, including the Metal Construction Association (MCA), are surveying members, developing positions and preparing proposals that could affect the final decision of the ruling code organization. In January 2002 the MCA enlisted the services of Jessie Beitel, a senior scientist with Hughes Associates, Inc., a fire engineering, research and consulting firm headquartered in Baltimore. He presented a detailed summary of the issues related to the perimeter joint fire testing and codes at the MCA's Semi-annual Meeting in Cleveland last August. Dan McGee, MCA's code consultant has also been involved in this issue. Both have prepared papers for review by the association.

Evolution of perimeter joint testing
Familiarity with the building industry's test development, promulgation, and code acceptance process is essential to understanding the complexities of the perimeter joint testing issue.

A number of organizations develop tests for building materials and submit them to code organizations for adoption. The most common are the American Society for Testing and Materials (ASTM) and Underwriters Laboratories Inc. (UL). In some cases, tests are created when manufacturers bring products to UL for performance evaluation. ASTM does not perform product evaluation, but disseminates tests by which products can be evaluated by various testing organizations. The key difference between the two organizations is that UL develops standards at the behest of manufacturers during development and examination of their products, while ASTM requires manufacturers to submit fully developed products for testing. It is common for both organizations, and sometimes the National Fire Protection Association, to be developing similar standards simultaneously.

According to Jesse Beitel, joint testing has been under close examination for a number of years. Two key joint tests that were developed at approximately the same time, UL 2079 and ASTM E-1966, examine the fire resistance of materials in joint systems by measuring the performance of fire-stopping material in a variety of joints.

In previous fire-safing material tests, the safing material was typically lodged between two concrete slabs. Countless materials have been tested in this way. In the late 1990s, UL decided to reorganize its Fire Resistance Directory into different applications. (This UL guide lists its certified fire-resistive products.)

The change meant that firesafing would no longer be tested on its own. Instead, it would be examined and classified in terms of end use-including perimeter joints, the area where a vertical curtain wall meets a horizontal floor.

Thus, says Beitel, the current controversy surrounding perimeter joints was born. The IBC Section 712.4 requires that such a joint be filled with fire-resistive material, and that the fire-safing must maintain the same fire rating as the floor material. But, explains Beitel, as UL began to separate and classify different kinds of fire-safing material applications, questions arose regarding the variety of curtain wall fire ratings: what would happen, for instance, when instead of monolithic concrete, the curtain wall was made of glass or aluminum? Testing showed that with some types of curtain walls, during a fire situation, fire-safing might stay in place, but the wall would warp, melt, or shatter.

Some fire-safing manufacturers say this problem can be solved by attaching vertical insulation on the back face of the wall system, both above and below the floor line, creating a barrier referred to as "aspandrel panel" in IBC section 704.9. These manufacturers began working with UL to develop standards for consideration as perimeter joints.

At the same time, ASTM began to develop its own perimeter joint test, which is still in development. UL and other laboratories used their own test method, based on the unpromulgated ASTM test, to evaluate and certify manufacturers' systems as perimeter joints.

The end result: while neither organization's perimeter joint tests have been accepted into the IBC, UL now lists certified perimeter joints in its Fire Resistance Directory. Manufacturers, in turn, promote their certified systems as an improvement over the codespecified fire-safing standards. The outcome is higher costs. "The price has gone up-in terms of both material and labor, " says Beitel. When architects specify the perimeter joint systems, costs are higher than if they had followed the fire-safing dictated by code.

What's next?
As things stand now, there is a real possibility that one or both of the perimeter joint tests will be promulgated, and therefore used to measure the performance of not only fire-safing in perimeter joints, but of the adjoining walls. For a large number of wall panel manufacturers, this would necessitate tens of thousands of dollars in re-testing for each wall system they manufacture to ensure UL or other laboratory certification. For most companies, it is an unavoidable cost, and for some it could climb well into six digits.

We spoke with several manufacturers and industry experts, some of whom believe this would be an acceptable evolution of the code. After all, they argue, traditional fire testing has shown that in some cases wall systems are inadequate. Others say they can accept the idea of a perimeter joint test- as long as it accommodates a wide variety of applications and the metal construction industry has a voice in developing those tolerances. Finally, there are those who argue that traditional test methods were sufficient, and that no test should be promulgated and accepted into code.

The Metal Construction Association is examining the issue extensively as it prepares its formal position on the issue. At the MCA Annual Meeting in January, Dan McGee presented recommendations that call for MCA to defend the current requirement and encourage other associations to work with MCA in opposing the inclusion of the new test into the building code. It was also noted at the meeting that the IBC code is not currently enforceable because there is no ASTM test to enforce it. The Association plans to have its position on code proposals ready for the ICC by the March 2003 deadline.

Beitel feels that MCA's stance is a key in this issue. "If the tests are accepted, MCA has to play a very significant role in terms of how those tests are used in the code," he says.

Paul "Kit" Emert, Jr., president of MCA and general manager of the Architectural Systems Business Unit of Fabral, sums up the Association's position. "Anything that affects the potential installation and application of metal wall panels is a serious issue. For the well-being of our members' customers, we will work to make sure that metal is treated fairly as we know their customers value the benefits of our members' products. We are confident that when used in proper applications, metal wall panels will meet or exceed the fire-safing requirements, and we will make sure that metal is put in the best light in terms of potential applications. We're doing everything we can to protect the membership of the Association and its customers."

Code organizations: a primer

U.S. building codes are designed to protect public health, safety, and welfare, and to minimize property damage and destruction through the establishment of minimum construction requirements.

For many years, three code organizations worked separately to create regional building codes: Building Officials and Code Administrators International, Inc. (BOCA), Southern Building Code Congress International, Inc. (SBCCI), and International Conference of Building Officials (ICBO). In 1994, representatives of these groups formed the International Code Council (ICC), with the goal of creating a national code without regional limitations.

In 2000, officials took an important step toward that goal with the creation of the International Building Code (IBC). Finally, in January 2003, the three organizations formally merged into the ICC. Model codes created by the ICC form the basis for all local codes, which individual states may choose to mandate.

Contractor educates officials about steel framing

When it comes to steel-framed homes, Duane Sieb, head of Residential Steel Construction Services (RSCS), Highland, Ind., is one of the industry's most vocal enthusiasts- and not just about building them. Sieb has made it his mission to spread the word about code requirements, safety issues, and construction techniques related to steelframed homes. And he does it all for free.

"I think it's so important to get the word out about steel," he says. Since founding RSCS with his sons Kent and Scott in 1997, Sieb has dedicated a large portion of his time to presenting his seminars to building inspectors, fire officials, vocational teachers, homeowners, and others. He has reached about 1,000 people in the last six years.

The issue of codes is always up for discussion when Sieb meets with building officials. At several of the Indiana Association of Building Officials' annual conventions he has given a "full-dress" seminar with demonstrations and a steel-framed building. Although he doesn't feel his work has affected how codes are accepted or created, Sieb thinks it has helped officials better understand and enforce the codes. This makes for a friendlier climate for builders using steel, he says.

For building officials he provides copies of the prescriptive method standards published by the American Iron and Steel Institute, a tool Sieb feels ensures a thorough understanding of code requirements. "It really simplifies the process and helps building officials understand what they're looking for when they go out to make an inspection. Prior to this, they have been in the dark. Even now, I get calls from building officials who say, 'I've got a steel building to inspect and I don't know where to start. Can you give me a hand?' And I'll go walk the building inspector through it, showing him what to look for."

"I think this has really helped building officials. I give them the key points to look for. Then they have more confidence going out on the job. Let's face it-some builders will try to buffalo an inspector, and if the inspector doesn't know what's going on in the industry, he's easy to buffalo. It's also for the good of the community. The consumer isn't aware of what's going on. It's got to start with the building inspector."

For fire officials and firefighters, he says, the focus is clear: "They need to know what some of their options are if they have to break through a wall or try to escape from a burning house." Using a slideshow, Sieb shows firefighters what they can expect in a steel-framed home. He also reviews fire test research published by the North American Steel Framing Alliance and the National Association of Home Builders and distributes supporting materials to firefighters and officials. Sieb thinks it helps them understand the structures for application to emergency situations.

With vocational teachers Sieb takes a different approach. He often brings tools and construction materials to give them hands-on experience in framing a house. Sieb says he will continue to teach wherever he is needed: "I'm trying to promote steel framing in every possible way I can. It's one of the things I enjoy doing, and I'll go talk about it any place people want me."

For more information on Residential Steel Construction Services, visit its website at www.residentialsteel.com.