Why Does Mold Grow in Corners of Rooms?

A corner can be the first visible sign of a leak inside the wall. A slow drip from a pipe, a roof leak, or a failing window seal can send water down the framing and pool at the corner. The drywall then wicks that moisture outward, and mold appears at the seam.

If the corner stain is brownish or the paint is bubbling, a hidden leak is likely. You can check the area with a moisture meter if you have one, or press on the wall to feel for soft spots. Finding the source early prevents bigger damage.

• Check for dripping pipes or condensation on cold water lines
• Inspect window seals and frames for gaps or water stains
• Look at the roof and gutters for signs of overflow or leaks
• Feel the corner for cold spots that suggest poor insulation
• Watch for peeling paint or dark streaks along the corner seam

Small patches of mold on non-porous surfaces like tile or painted wood can be cleaned with a mild detergent and water. Wear gloves and a mask to avoid breathing in spores. Scrub gently, then dry the area completely for a few days.

If the mold is on drywall, cleaning may not be enough because the spores can soak into the material. Porous surfaces often need to be cut out and replaced. For larger patches, a mold professional can assess the extent and suggest the right approach.

• Use a spray bottle with water and a few drops of dish soap
• Wipe from the outside of the stain toward the center
• Dry the area with a fan and keep it ventilated
• Discard sponges or cloths that touched the mold
• Seal the cleaned area with a mold-resistant paint if needed