How to Repair Drywall Corners to Perfection: An Expert Guide

A damaged drywall corner is more than just an eyesore; it's a weak point in your home's structure. Whether it's a chipped outside corner from a moving-day mishap or a cracked inside corner due to house settling, a proper repair is essential for a lasting, professional finish. At Executive Drywall, we know that the key to a perfect repair isn't just about covering the damage—it's about rebuilding the corner's structural integrity. This comprehensive guide will walk you through the precise steps and techniques used by professionals to fix any drywall corner, ensuring your walls are not only beautiful but also durable.

In this guide, you will learn:

• The different tools and materials required for inside versus outside corner repairs.

• Step-by-step instructions for repairing each type of corner.

• Pro tips and advanced techniques to ensure a flawless, long-lasting result.

By the end, you'll understand when a simple repair is a DIY project and when to call in a trusted local expert like our team at Executive Drywall to handle the job perfectly.

1. The Right Tools for the Job

Before you start, make sure you have the right materials. Using the correct tools for each type of corner is critical for an efficient and high-quality repair.

For Outside Corners (Where the Wall Sticks Out)

• New Corner Bead: This is the metal or plastic strip that forms the corner's sharp edge. It provides strength and a straight line.

• Snips: To cut the corner bead to the correct length.

• Drywall Screws & Drill: To securely fasten the new corner bead.

• Corner Trowel: A specialized tool designed to create a perfect 90-degree angle with joint compound. A 6-inch and 10-inch drywall knife can also work.

For Inside Corners (Where Two Walls Meet)

• Paper Drywall Tape: The industry standard for inside corners. Its crease in the middle helps it create a perfect angle and its strong paper material prevents cracks.

• All-Purpose Joint Compound: The "mud" used to embed the tape and smooth the surface.

• Corner Trowel or Drywall Knives: A corner trowel makes this job much easier, but a combination of 6-inch and 10-inch knives will work for feathering.

Universal Supplies

• Utility Knife: For scoring and trimming.

• Fine-Grit Sandpaper (180-220): Crucial for the final, smooth finish.

• Dust Mask and Goggles: Essential for safety, especially when sanding.

2. Step-by-Step Corner Repair Guide

Follow these steps to rebuild and repair your damaged corners.

Repairing an Outside Corner

• Remove Damaged Bead: Use your utility knife to carefully score along the edge of the old corner bead and gently pry it off.

• Cut and Install New Bead: Snip a new piece of corner bead to match the length of the corner. Secure it to the wall with drywall screws, ensuring it is plumb (perfectly straight).

• Apply First Coat of Mud: Apply a generous layer of joint compound to both sides of the corner bead. Using a corner trowel, smooth the mud over the bead, creating a clean, crisp line while removing excess compound. Let it dry completely.

• Apply Second Coat and Sand: Apply a second, wider coat of mud to blend the repair with the surrounding wall. Once dry, sand the entire area lightly with fine-grit sandpaper until it is perfectly smooth to the touch.

Repairing an Inside Corner

• Remove Damaged Tape: Using a utility knife, carefully peel away the old, compromised paper tape.

• Apply a Mud Bed: Apply a thin, even layer of joint compound to both sides of the inside corner. This will act as the adhesive for the new tape.

• Install New Tape: Take a piece of paper tape, fold it along its center crease, and press it firmly into the wet compound. Using your corner trowel, run it down the length of the corner to embed the tape and remove any excess mud. Let it dry completely.

• Apply Top Coat and Sand: Apply a second, thin coat of mud over the tape, feathering it out onto the walls. Once dry, sand lightly for a flawless finish.

3. Pro Tips for a Flawless Finish

The difference between a good repair and a great one is in the details. Follow these professional tips to achieve a seamless result.

• Go Thin, Not Thick: Always apply multiple thin coats of joint compound rather than one thick layer. Thick layers are more prone to cracking, shrinking, and bubbling, making a professional finish impossible.

• Feather Your Edges: With each new coat of mud, make your application slightly wider than the previous one. This "feathering" technique ensures that the repair blends invisibly into the surrounding wall.

• Utilize a Corner Trowel: This tool is designed to apply mud evenly and at a perfect 90-degree angle. It's a small investment that will save you hours of frustration and sanding.

• Be Patient and Let It Dry: The number one mistake DIYers make is rushing the drying process. Rushing will lead to a weak repair and visible imperfections. Let each coat dry completely—sometimes for 24 hours—before sanding and applying the next.

• Shine a Light: To spot imperfections, hold a bright light (like a work lamp or flashlight) parallel to the wall surface. This technique will cast shadows over any ridges or low spots you may have missed.

If you're not confident in your repair skills or are dealing with an extensive amount of damage, it's always best to call a professional. For drywall repairs and renovations of all sizes, contact us at Executive Drywall. Our team of experienced local contractors has the expertise to ensure your job is done right, the first time. We are your trusted partner for all drywall renovations in Edmonton and the surrounding areas.