White Powder on Basement Walls? A Practical Guide to Efflorescence and Moisture Control

Cleaning alone won’t solve the problem if moisture remains. To remove visible buildup safely, start by dry-brushing loose deposits with a stiff nylon brush. For more persistent areas, apply a mild solution of water and white vinegar, scrub gently, and rinse thoroughly. Avoid harsh chemicals or wire brushes that could damage masonry. After cleaning, focus on prevention: extend downspouts at least six feet from the foundation, ensure the ground slopes away from your home, seal visible cracks, and repair any plumbing leaks. Indoors, use a dehumidifier to maintain humidity below 50% and improve airflow with proper ventilation.

If efflorescence persists despite these measures, consider consulting a professional. Ongoing mineral deposits may point to deeper foundation cracks, drainage failures, or hidden water intrusion. In some cases, breathable masonry sealers or waterproof coatings can add protection—but only after moisture sources are corrected. Make basement checks part of your regular home maintenance routine, especially after heavy rain or seasonal changes. By addressing both the surface residue and the underlying moisture, you can keep your basement walls dry, clean, and free from recurring powder.