When you are renovating you will often have to plan for drywall replacement. This could be because the original drywall is damaged, you are restyling the wall or maybe you have to take off a section to fix a pipe. There are many reasons that a piece of drywall has to be taken off and replaced. Often it is easier to replace a wall than to repair a lot of damage.
You need to prepare for the enormous amount of dust that is produced by cutting and sanding drywall. This dust is very fine and gets into everything. Put down drop cloths and close any cabinet doors. Use masking tape to cover vents from heaters or air conditioners. Cover any furniture (or remove them) and also any knickknacks.
Cut off the power to the room and remove all electrical outlets and fittings. Remove crown and base moldings. If the crown molding is difficult to remove, just cut the drywall below it to remove the sheets.
2. Remove the Original Drywall
If you're removing damaged sheets, use a stud finder to check for wiring or pipes behind the section and then punch two holes in each sheet with a hammer. Use these holes to grab the sheet with your hands and pull. The sheets should come away from the nails in the studs.
For removing sheets whole so they can be reused, get a pry bar and gently lever the sheets away from the nails on the studs. Run your bar up and down all the studs to locate and remove all the nails. If the sheets are held on with clips, it's much easier. Just remove the sheets from the clips and then unscrew or pry out the nails holding the clips to the studs.
If you're just removing a section, don't be tempted to cut a sheet down the middle of a stud. This leaves little room to attach the new piece. It is better to cut just one side of the stud and screw a piece of 2 x 4 inch timber to the stud to refasten the sheet to.
3. Install New Drywall
Before replacing the drywall sheets, check the studs for termite or moisture damage. You can also take this opportunity to repair any torn insulation that is attached to the studs.
Making sure your new drywall sheets are the same size as the originals, attach them to the studs in the same way. Nails or screws are placed about every 16 inches.
Apply a good amount of joint compound to all the seams. Prepare and apply the drywall tape to the seams. Use your tape knife to flatten the tape, dipping the blade in water between each swipe. Allow the freshly taped joints to dry.
Apply at least two more coats, allowing it to dry between each coat. Don't rush this procedure or the tape will bubble.
Sand the seams lightly with an electric sander. Don't be too heavy-handed or you will expose the paper tape. Hand sand the corners as a machine will bump the walls and create more damage that you will have to repair.
With a smooth finish, you can choose whether to texture it and then prime and paint the wall.