Black Spots on Your Walls? Here’s What It Could Mean

If you see dark spots forming in corners or on walls, don’t ignore them. It might look like dirt at first, but it could be mold—often caused by excess moisture and poor air circulation. Mold thrives in damp rooms like bathrooms, kitchens, and behind tightly placed furniture.

To tackle it, ventilate the room daily, clean with white vinegar or hydrogen peroxide (avoid vinegar on stone), and use a dehumidifier if needed. Move furniture away from walls to help airflow.

Prevent mold by improving ventilation, monitoring humidity (keep it between 40–60%), and using anti-moisture paint. Persistent spots may signal hidden leaks or insulation issues—contact a professional if they keep returning.

Or Is It Spider Poop?

Tiny black dots along walls or skirting boards might actually be spider droppings. They’re usually dark, liquid-like stains found under webs. While not dangerous, clean them with disinfectant and wash hands after. To stop it for good, remove webs and consider pest control.