How Do You Know If Your Home Has Mold From an Old Flood?

Mold often shows up as black, green, or gray patches on surfaces. You might see it on drywall, wood, or grout. A musty odor is another clear clue, even if you cannot see the mold. That smell means spores are active somewhere in your home.

Check areas that stayed damp after the flood, like the bottom of walls, behind furniture, and under sinks. Discoloration or bubbling paint can also hide mold underneath. If you live in Detroit, pay extra attention to rooms that stay humid, since moisture can hang around for weeks.

Do not rely on sight alone. Mold can grow inside wall cavities or under flooring where you cannot see it. A persistent musty smell is often the first warning that something is growing out of sight.

• Dark speckling on drywall or ceiling tiles
• A damp, earthy smell in a specific room
• Discolored or bubbling paint on walls
• Soft or crumbling drywall near the floor
• Visible growth on baseboards or door frames
• Allergy-like symptoms when you are home

You can do a simple check at home. Wipe a surface with a damp cloth or use a store-bought mold test kit. These kits can tell you if spores are present, but they do not always show where the problem is. A positive result means you should look deeper.

Another method is to tape a piece of clear plastic over a suspicious area for a few days. If moisture collects underneath, that spot likely holds dampness. You can also use a moisture meter to check walls and floors for hidden water.

Keep in mind that a negative test does not mean your home is clear. Mold can be patchy, and a single sample might miss it. If you have any doubt, a professional inspection is the most reliable way to find the source.

Once you find mold, the first step is to remove the source of moisture. Fix any leaks and dry out the area completely. Use fans, dehumidifiers, and open windows to lower humidity. In a humid climate like Detroit's, keeping indoor humidity below 50 percent helps prevent regrowth.

Remove and replace porous materials like drywall, carpet, and insulation that got soaked. These items cannot be fully dried out. Clean hard surfaces with a mold-killing solution, and seal any cracks where water might enter again.

Check your home regularly for signs of dampness, especially after heavy rain or snowmelt. If you had flooding before, consider installing a sump pump or improving drainage around your foundation. Acting quickly can stop mold from coming back.