Get matched with top drywall pros in Forest Park, GA

If your home was built before the 1940s and was not remodeled in the past 50 or so years, you probably have plaster walls. Aside from assuming, there are some practical ways to tell if you have plaster walls, including the following: If you knock on the wall and it feels solid, not hollow, if you can’t insert a thumbtack easily, if there are cracks that look like spiderwebs, or if your home has curved, arched, or swirled walls, doorways, or window openings.

If you have an unfinished basement or attic, you could examine the backs of any finished walls to check, too.

All plaster walls will crack over time due to normal house settling and expansion and contraction from temperature and moisture changes. Small, thin hairline cracks are generally not serious and are mostly a cosmetic issue. However, larger or more significant cracks can indicate structural problems.

Here's how to tell the difference:

• Cosmetic Cracks: Cracks that are 0.5 cm (0.2 inches) or thinner are typically cosmetic.

• Structural Cracks: Cracks wider than 0.5 cm, excessive or deep cracks, multiple cracks in the same area, or cracks that span around corners can signify a structural or foundation issue. Cracks along the joints where walls meet the ceiling also warrant attention.

For cracks wider than 0.5 cm, structural repair is needed. If a crack is 2.5 cm (1 inch) or wider, or if you notice any signs of a structural problem, it is best to contact a plaster repair professional to assess the damage.

If you suspect black mold is inside your walls, do not punch a hole in the drywall yourself to look. Call a mold inspection expert to help you. Some signs of a potential black mold infestation inside the wall include an unexplained musty, damp smell. Some people liken it to rotting vegetables. You may smell it most strongly through a wall outlet. If you and your family are experiencing constant coughing or symptoms that feel like an unexplained allergy, it could indicate black mold behind a wall.

If you only have tiny holes in your drywall (for example, dents or nail marks), you probably won’t need a patch kit. Instead, you can plug the hole with a small amount of spackle. Once the spackle dries, you can sand the area and paint over it—just like you would in the steps outlined above.