A recent MCA study of the service life of unpainted 55%Al-Zn low slope standing seam roofing has had an impact on the Athena Sustainable Materials Institute. The report served as the technical substantiation for Athena to change the useful service life of this type of roofing product to 60 years! Athena’s software allows for whole building LCA assessment, taking into account all materials, systems, assemblies and components used in a given type of building.
MCA is part of a Zinc Coalition that was formed by IZA in the aftermath of the Washington Department of Ecology rainwater runoff project that was concluded in 2014. Misuse of the information related to zinc from the runoff report is influencing the Governor’s office and the legislative bodies.
Letter-writing advocacy, with guidance from IZA, is showing positive impacts. Several meetings have been scheduled with IZA and Coalition members to discuss the shortcomings in the runoff report and the outdated clean water regulations. MCA members that have facilities in Washington were asked to get involved in the effort. Similar issues are being seen in California, the Great Lakes region and in Canada.
The investigation of roof damage from high-wind events has shown that failure often initiates at the corners and/or edges of metal roofing. To address this situation, MCA has embarked on developing a test method standard that could be used to test the pullout strength of variations to edge perimeter details. A task group has developed a draft of the test method, which has been reviewed by several testing laboratories.
The next steps will be to test edge metal at different laboratories to determine if the test method is sound and repeatable among the laboratories. After testing and validation has been completed, the task group will create an industry guide and bring it to market. MCA will then pursue the ANSI standard process to create an industry standard. This is similar to the track that SPRI took for the development of their ANSI/SPRI ES-1 Standard.
Lawrence Berkeley National Laboratory was awarded a grant to conduct a research project on cool walls. This is important for California cities to find ways to reduce building energy usage and to help with the urban heat island effect. California already has a project investigating the impact of cool pavement. This wall project will evaluate the types of wall materials that are now in the marketplace. The performance of those products will be analyzed using outdoor exposure in three climates in California. In addition, the dirt-shedding capability and durability of these wall systems will be evaluated. New technologies for ultra-cool pigmentation are also part of the research, in the field of product development. The project begins in July with the product characterization on exposure racks. The entire project will take 3 years to complete. Several MCA member manufacturers are providing samples of their metal wall systems in this R&D program. MCA is also participating in the project in their seat at the Industry Advisory Committee.
The use of spray polyurethane foam insulation on single skin metal panels is being studied for wall and roof assemblies. A research project to evaluate the detrimental effects on metal was proposed with the Spray Polyurethane Foam Alliance (SPFA) and with the Metal Building Manufacturers Association (MBMA). Issues such as oil canning from the exothermic curing of the foam and related elevated temperatures is one such item to evaluate. Other concerns are centered around potential damage to paint films. As a collaboration among MCA, MBMA and SPFA, preliminary research has already been done to evaluate the exothermic curing on metal. The next phase will include the use of full size wall and roof assemblies with foam sprayed in different ways. Results of the project will be used to generate a “Do’s and Don’ts” guideline for using spray foam insulation with metal wall and roof assemblies.
As with all test standards, NFPA 285 is reviewed on a regular basis to address inconsistencies and technical issues within the standard. In March, an NFPA committee met and proposed changes to the wall construction for this test that will render many past tests invalid. The proposed modification specifically locates panel joints where they were previously required to be “representative of standard construction practices”. This modification will not only affect combustible exterior cladding, it will affect any wall assembly that contains combustible elements including insulation and barrier materials. The NFPA proposed modifications are currently open for public comment until November. During that time, MCA will work with NFPA to understand the reasoning behind this proposal and better define the level of impact.
Fastener Compatibility with Profiled Metal Roof and Wall Panels
Profiled metal roof or wall panels rely upon mechanical fasteners to secure the components to a structure. It is very important to select the correct type of fastener for metal construction in order to ensure a strong and weather-tight attachment. This Technical Bulletin serves as a guide for the selection of exposed fasteners used with metal roof and wall panels.
Download The Tech Bulletin > http://www.metalconstruction.org/download.php/education/user_file_2
Metal building, residential and roofing contractors, architects, engineers, developers, facility managers, fabricators and building owners from the US and abroad. Attend because it’s the only show of its kind in the world!