Angle beads are strips of thin sheet metal or plastic that are used to cover the outside corners of plastered or drywalled walls. They are long corner strips that are usually made of solid material right at the corner and made of perforated or meshed material at the edges. Angle beads are used to add strength to the corners of walls, provide sharp angles at the corner of a wall, and protect the corners against bumps and scratches.
Angle beads are often called corner beads in the construction trade. They may typically be seen in 8-foot (about 2.4-meter) lengths, which is a standard wall height in the US. Angle beads are only used on exterior corners and are not used on interior corners. Builders typically use drywall tape — which is made from a flexible, mesh material — to join the inside corners of walls.
The methods used to finish angle beads can vary. In general, the bead is screwed into the wall. After that, a series of thin coats of drywall compound or plaster are spread over the angle bead, allowed to dry, then sanded and re-coated to provide a smooth, finished appearance. Typically, three coats of drywall compound or plaster are applied and sanded before installation of the angle bead is complete.
Angle beading is not typically expensive. Price differences will largely vary depending on the material that the beading is made from. Galvanized angle beads may be more expensive but they often yield a sturdier result. Plastic angle beads may be easier to cut and may be less likely to leave sharp edges when cut.
Though angle beads are not required to finish external corners, they are generally preferred. Some come in strips that are already formed into a corner shape. Others come in flat rolls that have a self-adhesive backing. This type of angle beading can be rolled out, cut to length, and bent around the corner of the wall.