Achieving green building goals with architectural metal coating systems

Green building next-level programs

LEED v4.1

The LEED v4.1 Materials and Resources (MR) category provides several credit opportunities including material ingredient reporting and optimization; responsible sourcing of raw materials; waste reduction and management; life-cycle analysis with whole-building life-cycle assessment (LCA) and environmental product declarations (EPDs); and more.

Among the many paths to achieving this credit, LEED v4.1 also recognizes building products and materials providing health product declarations (HPDs) as part of the Building Product Disclosure and Optimization–Material Ingredients credit. Material composition must be reported down to 1000 parts per million (ppm) to qualify for LEED. The function of the substance and any information regarding impurities or residuals also may be reported. Specifiers with projects seeking to meet environmental goals such as LEED v4.1 certification should request the relevant documentation from their architectural coatings’ manufacturers.

Because coatings are an ingredient of the end product, only an HPD declaration can be given. However, once the coating is applied to the substrate, the metal building product manufacturer may be able to provide an EPD.

Living Building Challenge

Going beyond LEED certification, the International Living Future Institute’s (ILFI) Living Building Challenge (LBC) was launched by the Cascadia Green Building Council in 2006. Currently, it is considered the world’s most rigorous green building standard. Driven to develop a green framework for the 21st century, “Living Buildings strive for net-zero or net-positive energy, are free of toxic chemicals, and lower their energy footprint many times below the generic commercial structure. To be certified under the LBC, projects must meet a series of ambitious performance requirements over a minimum of 12 months of continuous occupancy.” As of May 2020, there were 134 certified and 686 registered ILFI projects from 34 nations.

Assisting building teams make informed decisions about material selections and specifications, ILFI also offers the Declare Label. Described as “an ingredients label for building products,” Declare Labels are active for 12 months, after which they must be renewed.

Products and materials labeled as Declare 2.0 include one of three declaration status indications for compliance with the LBC Red List Imperative and ingredient disclosure:

• LBC Red List Free products disclose 100 percent of product ingredients plus residuals present at or above 100 ppm (0.01 percent) in the final product and do not contain any Red List chemicals. They have been shown to meet the requirements of the LBC Red List Imperative.

• LBC Red List Approved products meet the written requirements but rely on one or more exceptions to demonstrate compliance. A minimum of 99 percent of product ingredients plus residuals present at or above 100 ppm (0.01 percent) in the final product are disclosed. The product may contain one or more Red List chemicals if they fall under an existing, published LBC Temporary Exception. They have been shown to meet the requirements of the LBC Red List.

• Declared products disclose 100 percent of product ingredients plus residuals present at or above 100 ppm (0.01 percent) in the final product but contain one or more Red List chemicals not covered by an existing Exception. ‘Declared’ labels require additional product research and vetting to locate a fully compliant product before it may be used on a LBC project.

Declare also has been approved as a compliance pathway for the LEED v4 and v4.1 Building Product Disclosure and Optimization Credit, Option 1. The LEED v4 and v4.1 credits call for the chemical inventory of a product to at least 1000 ppm; Declare labels that achieve a declaration status of ‘LBC Red List Free’ or ‘Declared’ fulfill the credit disclosure compliance requirements.

In addition, any fully disclosed ‘LBC Red List Approved’ label and any ‘LBC Red List Approved’ label using the I10-E4 Proprietary Ingredients Exception, with a minimum disclosure threshold of 99.9 percent, meets the LEED v4 and v4.1 Building Product Disclosure and Optimization Credit, Option 1 reporting requirements.

Declare has also been approved as a compliance pathway for LEED v4.1 Building Product Disclosure and Optimization Credit, Option 2. Declare labels achieving third-party verification and a declaration status of ‘LBC Red List Free’ fulfill the credit optimization requirements.

Red List ready

Silver Oak Cellars

Along with evaluating ingredients for potential concerns, innovative coatings manufacturers must ensure their formulations do not sacrifice expected performance, resilience, and reliability.

The source of a coating’s durability and physical properties is largely its resin; the resin’s primary function in a paint formulation is to bind all the components together. It increases the physical strength and chemical resistance of the coating film and allows for the curing process to occur. Architectural coating systems with 70 percent polyvinylidene fluoride (PVDF) resins (a type of fluoropolymer) meet the industry’s highest performance specification standard.

American Architectural Manufacturers Association (AAMA) 2605, Voluntary Specification, Performance Requirements and Test Procedures for Superior Performing Organic Coatings on Aluminum Extrusions and Panels (with Coil Coating Appendix), is published by the Fenestration and Glazing Industry Alliance (FGIA) and was updated in 2020. They are tested to meet or exceed the equivalent of 10 years south Florida weathering exposure conditions for color retention, and resistance to fading, chalking, and erosion. In addition, AAMA 2605 requires 4000 hours of accelerated testing for salt spray and humidity resistance.

Currently, one manufacturer has formulated a 70 percent PVDF resin-based, high-performance, architectural coating system free of any LBC Red List chemicals. Both coil and extrusion coatings using this formulation are verified to meet AAMA 2605 performance standards, documented with HPDs for material ingredient transparency, and supported with CSI MasterFormat specifications.

Declare Labels, listing a life expectancy of 40 years or more, also have been issued when these specialized coatings are factory-applied to metal building products made with common metal substrates such as 55 percent aluminum-zinc coated sheet (AZ50) steel, aluminum, and hot dip galvanized (HDG) steel. The metal material may be manufactured with recycled content and, at the end of the finished product’s useful life on a building, it can be recycled and reused without degradation.

When paired with approved pretreatments, primers, topcoats, and backers, these coating systems can be used to deliver a finished product that is LBC Red List Free or LBC Red List Approved. Providing further reassurance these coatings would perform as specified, finished metal panels are being field-tested at outdoor exposure sites in Fort Myers and Daytona Beach, Florida. After four years, corrosion remained minimal on all systems.

Leave a Comment

Comments

Your email address will not be published.