Round corner beads are used to create rounded corners on interior walls. This style adds a soft, soothing look to homes and offices, and the decorative feature mimics the rounded corners of adobe-built houses. Most drywall contractors can install a round corner bead with adhesive and drywall mud. Once dry and sanded, the corner blends with the rest of the room. Paint it or apply wallpaper to finish the newly decorated wall.
Purchase PVC or paper corner bead and corner adaptors for the top and bottom of the corner. These adaptors convert the round corner to a straight or right corner for baseboards and trim work. Buy some spray on adhesive for the PVC bead. Look for adhesive that is designed for hanging PVC bead.
Measure the height of the corner from top to bottom. Cut your round bead to length, making sure to include the lengths of the two corner adaptors.
Coat the sidewalls of the corner with adhesive or mixed drywall mud. Thoroughly coat the walls with adhesive for the PVC bead, although the paper beads only require mud to stay in place. PVC corners are more durable and last longer than the paper corners.
Press the round bead into place over the corner with flaps positioned along either sidewall. Hold the PVC bead in place for several seconds, pressing on the flaps to ensure a strong hold. Press the paper bead into place and scrape down the flaps on either side with the drywall knife.
Apply a layer of drywall mud over the corner and 6 inches into each sidewall. The bead will stick out about half an inch. You'll need to add that much mud to the wall to blend the rounded corner into the sidewalls. Scrape any excess drywall mud from the round corner as you go to ensure it stays smooth and rounded. Allow this first coat to dry.
Apply a second coat of drywall mud to the corner and both sidewalls. This coat will blend the newly rounded corner with the rest of the room. Apply drywall mud over the corner, continually scraping away excess to create a smooth transition. Allow the mud to dry for several hours.
Sand the corner lightly with a sanding block to smooth it. Apply a third coat of drywall if needed. Sand again after the third coat is dry. You can now paint the round corner bead.