Submitted by Jim Nisted, Dryvit Systems, Inc. for publication by CSI 4/1/2106
Originally published on Technical Services Information Bureau in February, 2009.
Corner reinforcements (corner beads) provide protection for outside corners of gypsum wallboard systems. The exposed nose of the bead forms a screed for finishing, adds rigidity and provides a straight line. Corner beads are available in a number of shapes and types from square edge to bull-nose configurations. Corner beads may be made from steel, aluminum, PVC and may have integral paper flanges or solid flanges with perforated holes. Some corner beads use joint compound to hold them in place, some require nails, staples and/or screws, while othersmay use a crimping tool (piercing the attachment flange into the gypsum board). Tape-on or a crimping attachment method are recommended for metal framing.
FRAMING AND GYPSUM WALLBOARD:
Framing must be true and the gypsum wallboard installed correctly to provide an acceptable base for corner bead attachment. If excessive gaps exist, longer leg (flange) corner bead may be used to cover the gap or the gap can be pre-filled with setting type joint compound. Gaps that will be completely covered by the solid part of the corner bead flange are not deemed excessive.