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Most drywall corner beads are available in various materials, including metal and vinyl. Some corner beads are "paper-faced," but even their core components are usually made of metal or vinyl.
The traditional corner bead material, metal, has been used to finish outside corners for generations. They can be installed with screws or nails and are relatively durable. But while metal corner bead has been used for a long time, that doesn't necessarily make it the best option.
The outside corners of your walls are extremely susceptible to damage because they are often kicked, struck or smashed, caused by anything from children playing to moving furniture. Metal corner beads will not shatter or break from this abuse, but they often dent. Once dented, the only way to repair a corner bead is to replace it, which is a time-consuming situation.
Additionally, metal corner beads are prone to rust and corrosion in damp locations such as bathrooms and basements, which can create longevity issues.
To make matters worse, metal corner beads are susceptible to denting, bending and damage before even reaching the jobsite — this can happen as easily as being jostled too much in the back of the truck on the way to work — wasting precious resources.
While metal is the traditional material used for corner beads, vinyl is the contemporary preference for modern drywall contractors and DIY enthusiasts.
Modern vinyl types of drywall corner beads provide significant advantages over their traditional metal counterparts, including, most importantly, durability.
Vinyl is virtually immune to denting and offers superior durability to metal types of drywall corner beads. This superb dent resistance results in a longer-lasting outside corner that maintains its visual and structural integrity far longer than its metal counterparts.
In addition to its dent resistance, vinyl’s flexibility allows it to combat damage or deformation from transportation. Plus, it maintains a consistent, straight edge during installation and finishing.
Vinyl is suitable for any wet, humid environment as it will not rust or corrode. Vinyl's natural flexibility allows it to absorb movement without creating the unsightly cracks that metal corner beads can create. This flexibility creates the ability to efficiently finish curves and other contours that are difficult for metal corner beads.
Paper-faced types of drywall corner beads are another modern solution to many of the problems produced by metal corner beads.
Paper-faced corner beads are installed similarly to how you tape your inside corners.
Lay a bed of all-purpose joint compound on either side of the outside corner.
Place a paper-faced corner bead on the outside corner of the bed of the joint compound.
Run a taping knife along either side of the corner bead to seat it firmly and remove any excess compound.
The paper-faced drywall corner bead was developed to eliminate the cracking and nail popping common in metal corner bead installations. Unfortunately, if not installed correctly, paper-faced corner beads can peel away from the wall, which results in an unsightly and unacceptable wall finish. Peeling can be difficult to remedy and often requires removal and re-installation.
In addition to the variety of materials used to make them, there are numerous drywall corner bead types, each with different profiles, purposes and functions.
A soft profile corner bead is one of the most common styles for residential and commercial settings. A slightly rounded corner profile provides a smooth visual appearance while still providing a gentle radius.
This sharply profiled corner bead provides precisely the aesthetic that its name implies. By creating a sharp outside corner, you can use less mud and no setback to finish it — saving you time and material.