Answers

John,

If it is a small repair, you may want to test out a product at Lowes.  Homax ceiling texture.  I'd suggest trying it on a scrap piece of drywall (make sure it's at ceiling height for testing).  Jayme and Phillip both had great ideas.  Perhaps yet another would be to just remove the popcorn all together.

Depending on what year your house was built, you might have asbestos in that popcorn ceiling. Typically, anything older than 1979 is a good chance that it could have asbestos; our company regularly finds that with popcorn ceilings. We always send a environmental hygenist out to our jobs to confirm whether or not a house is "hot" for asbestos. It's preventative protection for our workers.

Removing popcorn ceilings requires a lot of preparation to prevent contamination of the other areas of your home. You will need to cordon off the area (room) with some kind of plastic covering the walls, floor, and entry area - this is for your own protection. Also, you will need to wear personal protective equipment including a tyvex type of suit that covers you from head to toe, gloves, safety glasses, and most importantly - a respirator. These things are necessary to keep you safe from breathing in the microscopic fibers of asbestos and preventing you from getting asbestosis or mesothelioma (a tumor of the mesothelium, often malignant and thought to be caused most commonly by the inhalation of asbestos particles.)

Do you really want to do this.  If you have not done this before,, I would think about subing it out

Philip

Berkeley Ca

Supplies needed: 

hopper gun and compressor (available for rental at home-center stores), paint tray, paint suit and glasses, stepladder , putty knife, paint mixer, paint roller, masking tape, drop cloths, ceiling texture, primer sealer, spackle

Here are the steps you need to take to get the job done: 

1. Fill any dents or imperfections in the ceiling with spackle, and then apply a coat of primer with a roller. Allow the primer to dry at least four hours.

2. While it's drying, mask off the walls and floor with masking tape and tarps, plastic sheets or drop cloths. 

3. Wearing proper protective clothing and goggles, pour some texture mix into a large bucket and mix according to directions. Use a paint-mixer attachment to achieve a nice blend. The mixture is ready when it's the consistency of thick porridge.

4. Fill the hopper with texture mixture and fire up the compressor. Practice spraying on an old board or a large piece of cardboard to get the feel of the machine.

5. Lightly spray the mixture onto the ceiling, and keep moving to avoid oversaturating any area. Use multiple light coats and allow the texture time to dry between coats. If you spray the texture on too thickly, it will drip off the ceiling.