automatic walls folding walls acoustic Automatic Walls Skyfold Autolift Automatic Walls system has been tested by the National Research Council of Canada in compliance with ASTM E90 for sound transmission. The tests yielded an STC rating of 51 while individual panels obtained an STC of 54 as tested at Concordia University’s Center for Building Studies. Better yet, the system was shown to retain its sound-separation capabilities over the life of the wall! There are also a variety of panel finishes available that offer desired NRC properties.