How to Finish Drywall in a Garage
- 1). Check the temperature in the garage. For the mud and tape to bond correctly to the wall, the temperature must be at least 55 degrees Fahrenheit. If you are working on the garage in winter, use a space heater in the garage to achieve this temperature.
- 2). Run your 6-inch taping knife along all of the joints and listen for metal on metal contact. If you hear anything, drive the protruding nail or screw deeper into the drywall. Repeat for all joints to ensure that you will not be able to see the nails or screws once you seal the joints.
- 3). Cover any outside corners in your garage with metal corner beads. These metal bands will prevent the mud and tape from running off the corner and spreading down the wall. Hang these pieces on the corners with drywall screws.
- 4). Mix your joint compound (mud) with a paint stirring stick or a stirring attachment for your power drill. If you use the attachment, work on the lowest setting to avoid splashing mud. Mix for two to three minutes until the mud has a smooth but thick consistency.
- 5). Spread a thick layer of mud over the joint with your taping knife. Try to keep the layer at an even thickness as you work.
- 6). Spread paper tape across the mudded joint. Run the taping knife over the tape to encourage it to bond to the mud. Cover all joints with mud and tape in this way.
- 7). Spread a thin layer of mud over top of the tape to seal it against the wall. Allow this second layer of mud to dry for one hour before continuing.
- 8). Wipe at the joints with a damp sponge to smooth down any lumps and remove excess mud. When you've achieved a flat surface, allow the mud to dry completely overnight.
- 9). Finish the walls with paint or wallpaper. If you decide not to paint over the drywall, sand the joints lightly with fine grit sandpaper and apply a second coat of mud/tape/mud to completely seal the joints. Whichever method you choose, allow the final coat of mud or paint to dry for 24 hours before exposing the drywall to any moisture.
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