The Art of Building a Drywall Arch
Building a drywall arch is an art, but fitting drywall into a curve is where the professional contractor earns his money. To reduce time spent soaking a drywall strip into a curve, start by purchasing 1/4-inch drywall that’s designed to bend.
For building a drywall arch, start by using your cut-out wood pieces as your drywall pattern. After marking the arch on the drywall, frame a curved arch bend and fasten a strip of drywall to the curved framing. Attach your drywall side pieces to your wood framing after you mark the locations of the wood supports you need for the corner bead.
Cut the corner bead a full inch longer than you measure, and then cut off the extra after you put it up. After attaching the bead, run your taping knife over the edge to see if you can identify any protruding screws or tabs. Drive down any screws you identify.
Coat the piece thick enough to completely fill in the area from the corner bead to the edge of the wall. Use a wet, wide drywall knife to skim off the compound. Use the corner bead as a guide and glide your knife over it to skim the mud.
Before you apply the next coat, scrape down any bumps or ridges. Next, place a thin, 8-10″ wide coat over what you have already coated. This time, skim this coat off perpendicular to the corner bead, as opposed to using the corner bead as a guide.
On the inside of the drywall arch, place another coat, if needed, as done in Steps 3, 4, and 5.
Use light to see where you need to add any mud. If you have to, immediately skim it off with a 4.5-inch taping knife.
Lightly sand the wall with 200-220 sanding paper in a circular motion.
The final step of building a drywall arch is to clean the dust off the wall before you prime and paint.