What are my options for outside corner bead and how does each one get attached?

Here are your main options for outside corner bead and how they're attached:

Metal Corner Bead (Aluminum or Galvanized Steel)

• Attachment: Fastened with drywall nails or screws every 6-8 inches, or stapled if using light-gauge aluminum
• Best for: High-traffic areas, new construction

Paper-Faced Metal Bead

• Attachment: Embedded in joint compound - the paper flange gets mudded directly to the drywall
• Best for: Residential interiors, smoothest finish

Vinyl/PVC Corner Bead

• Attachment: Nailed or screwed through the bead, or glued with construction adhesive
• Best for: Moisture-prone areas (bathrooms, basements), lightweight applications

Flexible Corner Bead (Vinyl or Composite)

• Attachment: Adhesive-only or minimal fasteners, designed to flex with building movement
• Best for: Areas with settling/shrinkage concerns

Wood Block Corners

• Attachment: Wood blocks nailed/screwed to framing, then taped and mudded
• Best for: Traditional work, rustic finishes

Installation Tips:

• Always use setting-type compound for first coat on metal beads
• Paper-faced beads require 2-3 coats of joint compound
• Vinyl beads can be more forgiving on uneven walls
• For fire-rated assemblies, check UL listings - metal beads typically perform better

Code Note: Most building codes (IBC Section 104.11) require adherence to manufacturer specifications. Check local codes for fire-rated wall requirements.

Choose based on durability needs, moisture exposure, and your finishing skill level. Metal offers best protection; paper-faced gives easiest finishing.

1. Metal (Galvanized Steel)

• Best for: High-traffic, straight corners, impact resistance.
• Attachment: Mechanical fasteners only. Use 1¼" drywall nails (spaced 8–9" o.c.) or fine-thread drywall screws. Drive heads slightly below surface; do not break paper. Mud holds it after fastening.
• Code: ASTM C1047. Required for fire-rated assemblies (IRC R702.3.5).

2. Paper-Faced Metal (e.g., CertainTeed No-Coat, Strait-Flex)

• Best for: Eliminating cracked corners, off-angle corners, speed.
• Attachment: Setting-type compound only. Apply heavy bed of 20/45/90-min mud to both faces. Press bead in, squeeze out excess. No nails/screws. Paper tape bonds to drywall paper.
• Note: Must use setting compound for first coat; drying compound lacks bond strength.

3. Vinyl / PVC (e.g., ClarkDietrich, Trim-Tex)

• Best for: Wet areas (bullnose, shower curbs), curved walls, non-90° angles.
• Attachment: Staples, spray adhesive, or mud.
• Staples: ½" crown, 9/16" leg (pneumatic) every 8–9".
• Mud: Bed in setting compound like paper-faced.
• Adhesive: Construction adhesive for temporary hold before mudding.
• Code: ASTM D4216. Not for fire-rated corners unless specifically listed.

4. Composite / Hybrid (e.g., MudLock, Magic Corner)

• Best for: Maximum crack resistance, structural movement.
• Attachment: Mud-set (setting compound). Rigid plastic nose with paper/fiberglass wings. Embed fully in mud.

Critical Rules:

• Outside corners only. Never use corner bead on inside corners (use paper/fiberglass tape).
• Fastener heads on metal bead must be covered by first coat of mud.
• Gaps > 1/8" at drywall edges must be pre-filled with setting compound before bead installation.
• Fire-rated walls: Use metal bead fastened per manufacturer’s tested assembly (usually nails/screws 8" o.c.).

Pro Tip: For 90° metal bead, run a bead of construction adhesive down the drywall edge before nailing. It kills "clicking" movement and strengthens the corner.