Abstract:
Fibrous mat, e. g. glass fiber, having a sheet facing on one face is wound in continuous lengths with minimum tension, compression, shear and working during the winding and with a large open center. The coils are compressed by a straight line compression generally normal to the major face of the mat and packaged with greater compression than heretofore acceptable in view of the recovery of insulation thickness upon installation. Nearly complete recovery is experienced. Further, stresses on the coiled material during compression and packaging are insufficient to destroy the longitudinal integrity even when it is skip chopped in a manner which separates more readily than prior skip chopped strip. Skip chopped strip is perforated transversely for manual separation at the point of installation by cutting through the tab margins of the facing to the edges thereof and cutting through the mat and facing in a line leaving narrow columns of glass fiber backed by the facing to maintain the longitudinal integrity of the mat. A blade having cutting edges which sever the extremes of the facing margin for a plurality of simultaneously cut strips is employed.