How do you repair drywall outer corners?

Repairing drywall outer corners can seem daunting, but it’s actually a straightforward process if you have the right materials and follow some simple steps. In this article, we’ll walk through everything you need to know to patch up drywall corner damage and get your walls looking good as new.

What Causes Outer Corner Damage?

Outer corners of drywall are prone to damage for a few reasons:

• They stick out and are vulnerable to bumps, knocks, and scrapes from furniture or other objects in the room.
• The seam where the two pieces of drywall meet at the corner is weaker than other areas of the wall.
• Kids and pets running into corners can cause chips, cracks, and crumbling.

Over time, these impacts can break through the corner bead (metal trim piece) and paper layer of the drywall, exposing the brittle gypsum core underneath. Once this core is damaged, cracks and holes can quickly get larger.

Materials Needed for Repair

Before you start patching, make sure you have the following supplies on hand:

• Joint compound (sometimes called mud) – Pre-mixed all-purpose joint compound is the easiest to work with
• Joint tape – Paper or mesh tape designed for drywall joints
• Corner beads – Use paper-faced metal corner beads that match the existing corner style
• Drywall screws – 1 5/8″ screws work for most standard 1/2″ drywall
• Utility knife – For trimming corner beads and drywall
• Sandpaper – 120 to 150 grit for smoothing dried compound
• Paint – Match the existing wall color as closely as possible

You may also need a few basic drywall tools like a taping knife, mud pan, and pole sander. Having a power drill on hand makes installing corner beads much easier too.

Prepping the Damaged Corner

Start by cutting back any loose drywall or jagged edges around the damaged area using a utility knife. Cut at least 6 inches back from the corner on each wall to expose enough area to securely attach new corner bead.

If the damage extends down to the wall studs, also scrape or sand away any leftover joint compound or drywall shards so you have a clean surface for the repairs.

Applying New Corner Bead

With the damaged section opened up, it’s time to attach new corner bead:

1. Measure and cut a length of paper-faced metal corner bead slightly longer than the area you need to patch. It’s easier to trim excess later.
2. Hold the bead in place so the center crease aligns with the corner. The perforated flanges should extend at least 2 1⁄2 inches onto each wall surface.
3. Secure the bead with 1 5/8″ drywall screws driven through the flanges into the wall studs or drywall. Place screws every 6 to 8 inches.
4. Use a utility knife to trim off any excess corner bead sticking out beyond the repair area.
5. Make sure the bead sits snug in the corner – bend it slightly if needed so it’s perfectly aligned when you’re done.

Applying Joint Compound

With the new metal corner installed, it’s time to start applying joint compound:

1. Use a 4 to 6 inch taping knife to apply a thin layer of compound over the corner bead flanges. Smooth it out, leaving the perforated screw holes slightly exposed. Let this first coat dry fully.
2. Apply a second coat, using a wider 6 to 10 inch knife this time. Fully cover the first layer of compound, extending it approximately 8 to 12 inches wide on each wall. Feather the edges so the new compound blends evenly into the existing corner.
3. Let the second coat dry completely, then inspect for any indentations or gaps. Apply a third coat if needed to create a smooth, flush corner. Allow to dry thoroughly.

Pro tip: Apply thin coats and allow plenty of drying time in between to minimize cracking. Using a damp sponge or sanding block, gently smooth each coat as needed after applying.

Finishing Up

You’re in the home stretch once the corner bead is covered with several smooth coats of joint compound. The last steps are:

• Sand – Carefully sand the patched area, focusing on any dried drips or uneven spots from the compound. Use 120 to 150 grit sandpaper and be cautious of the paper on the corner bead.
• Prime – Before painting, apply 1-2 coats of drywall primer to help the paint adhere properly. Make sure to feather out the edges.
• Paint – Finish up by painting the repaired corner using a roller and brush. Plan on 2 coats to match sheen and color of the existing walls. Extend the paint several inches beyond the patched area to blend it in.

And that’s it – your damaged outer corner should now be repaired and ready to handle bumps and knocks again. Just take care not to ding it up too soon before the joint compound and paint have fully cured. With proper materials and some patience, drywall corners are easy to DIY.

Tips for Long-Lasting Corner Repairs

Here are a few extra pointers to help your fixed corners look great and avoid future damage:

• Consider metal corner guards if kids or traffic will be an issue. Surface-mounted guards protect vulnerable corners.
• Caulk between the corner bead and wall with paintable silicone caulk. This seals gaps and helps prevent future cracks.
• Use paper drywall tape instead of mesh tape – it provides stronger joints with less risk of cracking long-term.
• Make corner patches over 12 inches long to prevent future cracking. Overlap at least 6 inches beyond damaged areas.
• Take time with finishing steps like sanding and feathering paint for an invisible repair.

When to Call a Pro

While DIY works for minor corner repairs, it’s best to call a professional drywall contractor for more extensive issues like:

• Water or mold damage behind walls – This requires addressing underlying problems before cosmetic fixes.
• Significant corner cracks wider than 1/4 inch – May indicate structural issues needing inspection.
• Popcorn ceiling texture matching – Difficult to blend patches into textured finishes.
• Large repairs over 4 feet long – Time intensive for beginners to tackle.
• Damaged corner bead on ceilings – Overhead work is challenging.
• No corner stud access – Makes secure corner bead installation tricky.

Don’t be afraid to call the pros if a corner fix seems beyond your DIY skills. Professional drywall contractors have the tools, materials, and experience to repair any corner damage quickly and seamlessly.

Cost of Professional Drywall Corner Repair

If you do hire out drywall corner repairs, here are typical costs:

Corner Patch Size	Average Cost Range
4 ft or less	$100 – $300
4 ft to 8 ft	$300 – $500
8 ft to 12 ft	$500 – $800

Prices vary based on patch size, complexity, and your location. Expect to pay $100 to $500 per corner on average when hiring a pro. Get multiple quotes to find the best value.

Conclusion

Fixing damaged outer corners may seem difficult, but simply follow the step-by-step process:

1. Cut back damaged drywall and remove any debris
2. Install new corner bead flush with the corner
3. Build up thin coats of joint compound over the bead
4. Sand, prime, and paint for a finished look

Focus on quality materials, proper drying time, and neat finishing work for long-lasting repairs. Consider calling a professional if the corner fix is too large or complex for DIY.