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Long-spans amplify the collaborative relationship between architects and engineers

By: Richard C. Master, AIA, CSI
Chair Emeritus, Specifications and Building Technology, Professional Interest Area (PIA), AIA
Manager, Architectural Systems
USG Corporation

Acoustical Ceiling Panels

Some acoustical ceiling panels contain mostly mineral wool, gypsum and smaller amounts of paper and starch, as well as other miscellaneous materials. The recycled content in ceiling panels varies from approximately 20 to 80 percent, depending on the product type, manufacturing process and plant location. The mineral wool used in the panels is usually made from slag, a by-product of steel manufacturing that consists of calcium silicate and other impurities. The slag is melted in coke-fired cupolas or electric melters and spun into fibers, which are incorporated into the ceiling panel production process. The use of slag reduces the need to mine naturally occurring materials such as basalt rock. It also decreases landfill waste. A high percentage of the paper used in the manufacturing process is recycled pre-consumer (cuttings from cardboard box manufacturing) and post-consumer (newspapers). The starches used as binders in the manufacturing process are renewable agricultural resources.

Like gypsum board manufacturing, acoustical ceiling production is a low-waste process. Panels that are chipped or broken during manufacturing are recycled and returned to the process.

The steel suspension systems used to support ceiling panels are considered green because they can be more easily reused than wood. The suspension systems can be 100 percent recycled by remelting and salvaging the metal.

It is also worth noting that some acoustical ceiling panels are available with a limited warranty against mold and mildew growth, which can help promote indoor air quality (IAQ).

Gypsum Fiber Panels

The gypsum fiber manufacturing process combines gypsum and cellulose paper fibers to create a variety of high-performance panels, including floor underlayments and exterior sheathings. Gypsum fiber underlayment and sheathing panels are both made from 95 percent recycled materials. Specifically, 85 percent of the content in these panels comes from recaptured gypsum and 10 percent is from post-consumer recycled paper fiber. The panels offer an excellent sustainable alternative to other wood-based panels, most notably lauan, which is harvested from endangered, old-growth forests.