Removing a ceiling stipple is a process that can take several hours depending on the specific texture of the stipple and the size of the room. In order to remove this textural effect from your ceiling, you will need plastic sheets, duct tape, an air mask, a palm sander and a shop vacuum.
Protect your room
Using the plastic sheeting and duct tape, seal the room off from the rest of your home. You should also cover up your furniture and close your air ducts to protect them from flying dust. If the room has windows, open them to keep circulation flowing while you work.
Sand down the ceiling
Put your protective air mask on. Turn on the palm sander and begin sanding down the texture of the ceiling. When you hit the surface of the drywall, you can move on to the next patch. Make sure you do not press into the drywall, as this could damage your home.
Turn on your shop vacuum and use it to collect any of the dust that has fallen around the room. This will help to keep your home clean and to make sure you avoid breathing in any potentially harmful particles.