Truth in Numbers

The 640 Series panel construction provides architects and building owners with industry-leading acoustics. How do we know? We tested it and here's what we found.

The 640 Series panel construction provides architects and building owners industry-leading acoustics, with an STC rating of 56.

We have the test results to back it up. In fact, take a look for yourself.

We can say that because it’s true. When testing operable walls, it is very important that the entire installation is tested-not just a section of an individual panel. The results are very different when testing is performed incorrectly.

The 600 Series 56 STC panel requires Hufcor standard top and bottom “quick-set” mechanical seals. The quick-set seals are activated on the panel’s edge with a half-turn of an operating handle and are spring-loaded to absorb building movements to maintain a tight acoustical seal in the field. Hufcor’s top and bottom mechanical seals are durable and housed within the panel, unlike bayonet-type plunger “automatic seals” that are susceptible to damage. And the Hufcor seal system is far faster to operate using a quick half turn instead of multi-crank down seals that require up to eleven (11) rotations per inch of seal distance.

Hufcor has long been the leader in acoustic performance among operable partition manufacturers. Since 1969, Hufcor has owned and operated a National Voluntary Laboratory Accreditation Program (NVLAP) accredited acoustical lab in Janesville, Wisconsin and tested both our own products and that of other global manufacturers. Hufcor is the only operable partition manufacturer and one of only eight U.S. companies (IBM, 3M, Owens Corning, Dell, John Mansville, Armstrong, USG) that has their own lab for continual testing of STC and NRC (sound absorption). Hufcor engineering staff members participated in the ASTM E-33 Committee that sets the testing standards for both laboratory and infield acoustical test procedures. The 600 Series 56 STC model was tested using the newest ASTM E-90 standard, following all of the newest upgraded procedures recommended by the E-33 committee.

The 56 STC 600 Series panels are limited to both paired and omni-directional panels, and not available for use on continuously hinged electrically operated panels.
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