Black Spots on Your Wall? Here’s What They Might Be 1. Mold A small black patch
could be mold, not dirt. It often forms due to moisture, poor ventilation, leaks, or blocked
airflow behind furniture. What to do: Ventilate rooms daily. Clean with vinegar or hydrogen
peroxide (avoid vinegar on natural stone). Move furniture slightly away from walls.
Use a dehumidifier if needed. Prevention: Install extractor fans.
Monitor humidity (ideal: 40–60%). Use anti-moisture paint. Fix leaks or insulation issues early.
2. Spider Droppings Small black specks might also be spider poop. It looks like dark ink stains,
usually found under webs or in corners. Key facts: Not solid—thick, liquid-like stains. Colors vary
(black, gray, white, or brown). Usually not harmful, but clean carefully and wash hands. Solution:
Remove webs regularly. Keep the home clean. Use pest control if needed. Bottom line: Black spots
could signal mold or pests. Don’t ignore them—clean up, investigate the cause, and take action to prevent future issues