However, prolonged exposure to moisture can more severely alter the appearance of your walls. Additionally, mold and mildew thrive in damp environments and can form on a water-damaged wall. If your drywall has patches of gray, black, brown, and/or green, you might have a mold problem.
Water Stains
Though it might not show for a while, the moisture in the drywall will remain and spread, flaking away from the paint or changing its color.
Surfactant leaching, or the appearance of brown residue or streaks on interior and exterior painted surfaces, is a common problem that occurs when painting with water-based latex paint.
Dirt and Dust
Regardless of the quality of your air filter, there are many impurities in the air inside your home. You may not notice the appearance of dirt, dust or pollen, but these tiny particles accumulate on walls. Over time, these areas start to take on a different hue than other spots in your house.
“The brown beads are most likely the result of surfactant leaching. The moisture and steam from showering can cause it to separate from the paint mixture and diffuse into the paint's surface, causing dark spots and droplets.”
Tannin staining is the brownish or tan discoloration on a painted surface due to migration of tannins from the substrate through the paint film.
As noted above, water damage will usually leave walls soft to the touch, or otherwise warped, buckled, and crumbled. It also tends to cause a musty smell and dark brown or yellow-tinted stains, lines, or rings in both ceilings and walls.
The most obvious sign of water damage in the wall is discoloration or stains on your walls or ceilings. These stains can start small and grow if the leak isn't discovered and addressed quickly. If your walls or ceilings are white, you may notice a beige or brown spot, which is a clear indicator of water damage.
They often appear grayish-black. However, other types of mold can also be orange, purple, yellow, and green in color. If your property had just been flooded, observe the porous, organic surfaces like drywall, plywood, and fiberglass insulation backing that had been submerged in water.
Another apparent sign of water damage is if your drywall feels mushy or softer than normal. If the water absorbs into the drywall, mold can start to grow within a few days. In that case, you'll need to reach out to a contractor to remove and replace it.
The drywall absorbs water and can cause mold to form, which damages the drywall further. Whether your drywall water damage is from a roof leak, air conditioner, flooding, or something else, repairing the water damage must happen quick.
Typically, the black or brown stains are caused by high levels of manganese. These colors can have a lot in common with some of iron-staining issues because both manganese and iron show up in well water. Like before, even water that appears to be clear can still cause stains.
An iron analysis will tell you if this is the cause of the stain and just how much iron is in the well water. Light brown or tea-colored stains: Usually caused by manganese. Manganese is also a common component in the Earth's crust and is also found in many ground waters.
Signs and Symptoms of Hard Water
There are several telltale signs of hard water in your home or business: Soap scum buildup in your tub or shower. Brown or reddish stains in your sinks, showers, and toilets. Additional soap required to get your body, laundry, and dishes clean.
Water Damage
A big question homeowners often ask is “does wet drywall always need to be replaced?” and the answer is almost always yes.
To identify water leakage in your walls, look for signs like musty odors, mold growth, new or worsening stains, peeling or bubbling paint or wallpaper, buckling ceilings and floors, wet or discolored areas, the sound of dripping water or warped sheetrock.
If your drywall is absorbing moisture, you might notice the dark, spotty stains that indicate mold growth. You may see some fuzzy growth, or irregular spots ranging in color from brown or black to green and even pink.
Mold growing on wet drywall follows a similar growth pattern as on other surfaces; within two days (or about 24 to 48 hours) of water intrusion, mold will begin to colonize damp drywall and release new spores. One thing to keep in mind, however, is that drywall is extremely porous, so it has a high absorption rate.
Additionally, if left untreated, water damage on walls can cause the surface to crack, peel or buckle. This can create both cosmetic and structural issues. Water damage can also give host to mold and mildew. That's why repairing water-damaged drywall in a timely manner is best.
If you see any brown spots on your ceiling or walls, it is a water stain most likely caused by a leak. A water stain is typically created by a leak from your roof, heating appliance, or plumbing leak.
If you haven't noticed brown spots or streaks on your bathroom walls in the past (or anywhere else in your house), but start to see them after recently painting, the problem could be something called surfactant leaching.
Most instances of brown shower water are caused by iron and sediment deposits. of iron, you may notice that your toilets, sinks and clothes develop brown, rust-like stains.