Plaster is a durable building material that has been used in construction since ancient Roman times. It's still popular today but is most often found in older homes. As a result, the material can be affected by time and age. If your plaster walls have turned brown or become discolored, you may have to contact a plaster repair service that can restore their original color. The following guide offers an explanation of why plaster turns brown and what you should do about it.

What Causes Plaster to Turn Brown?

Discolored plaster is an early sign of water damage. Moisture from a roof leak or dripping pipe often contains dirt, rust, or another sediment. When dirty water seeps into the wall, it causes the plaster to turn brown. 

You may observe other symptoms, as well. For instance, paint on the surface might start to flake or bubble outward. Sometimes, the stains can be caused by mold. While it does not feed on plaster the way it does on drywall, it can feed on paint or dust on damp plaster surfaces. Although stains and other problems may appear without warning, it usually means a leak has been occurring for some time. 

What Can You Do to Fix It?

Mix a solution of 1 cup ammonia, one-half of a cup vinegar, and one-fourth of a cup baking soda into a gallon of water. Apply the mixture to the stain with a sponge or washcloth, and rub firmly in a circular motion for several minutes. This can help remove the contaminants and bleach the surface. Dry the plaster thoroughly afterward.

If the discoloration still remains, you can repaint the surface and cover it with a stain-blocking primer. However, be aware that neither of these solutions address the underlying problem of excess moisture. To prevent further discoloration and additional property damage—like swelling or rotting lath—you will need to have a professional fix the leak. Consult a plaster repair contractor before taking any do-it-yourself measures to ensure you won't accidentally damage the surface further.

If you need plaster repairs to eliminate stubborn discoloration, reach out to the experts at Old World Plastering. This family-owned and -operated company offers plastering and historic preservation services to homeowners and commercial property owners throughout Greater Cincinnati, OH, and the Tri-state area. They also specialize in moisture intrusion, statue restoration, and ornamental design. Owner Greg Colina is personally on-site at every job, and he and his team guarantee their work and results. Learn more online, or call (513) 481-1122 to schedule plaster repair.