Paint Flaking off your Ceiling and Walls? Calcimine Could be the Culprit

Shannon Lee

Is the plaster ceiling in your old house peeling like mad? Are long strips of white, chalky paint flaking away? You might have calcimine ceilings. Very affordable and readily available, calcimine was once widely used to provide a quick and attractive finish to plaster ceilings and walls.

Calcimine is essentially chalk; it is made of dried calcium carbonate mixed with water, glue, and the occasional pigment. Because calcimine has no binder chemicals, it doesn't provide a proper surface for modern paint. Try painting over it and you get the problem of peeling and chipping paint.

How to Repair a Calcimine Ceiling

If your calcimine ceiling is looking a bit rough, it's time for an overhaul. The best way to handle calcimine is to remove it altogether. These step-by-step tips can help make the job easier:

  1. Start by removing the paint that is peeling and chipping away. Using a putty knife, scrape the paint away from the plaster. Depending on the type of paint and how many layers were used, the difficulty of this job may vary. You know you have reached the calcimine layer when the particles become very fine, and the surface feels like schoolhouse chalk on a board.
  2. Wash the surface with water and plenty of detergent. You want to create a sudsy solution on your ceiling in order to pull the chalky residue away from the plaster. Use a large sponge or squeegee tool to remove the foam and water.
  3. Repeat the washing and scrubbing several times. When you think the job is done, test it by rinsing with water and a clean sponge. If the water in your bucket is not clear, go back to washing and scrubbing until it is. A little patience goes a long way at this point!
  4. If there is any damage to the underlying plaster, now is the time to fix it! Don't be surprised if you find more chalk on the ceiling after it has had time to dry; calcimine lingers, no matter how many washings and scrubbings you give it.
  5. When you're ready to repaint your plaster ceiling, start with a calcimine-coater paint. These paints are designed to penetrate any remaining calcimine and seal it to the plaster, leaving you with a clean, smooth surface on which to add additional paint if you choose. Many calcimine coatings require only one layer of paint.

Once you've completed your "renovation," your old house plaster ceiling should eventually take on a yellow tint to maintain that beautiful historic look.


About the Author

Shannon Dauphin is a freelance writer based near Nashville, Tennessee. Her house was built in 1901, so home repair and renovation have become her hobbies.

Search Improvement Project