Odors in crawl spaces can be persistent, even after thorough cleaning and sealing. Factors such as humidity, ventilation, and the presence of mold or pests can contribute to this issue. It's essential to consider the materials used in sealing and the effectiveness of your ventilation system. Regular maintenance and monitoring are key to preventing odors from returning. Curious about the best practices for keeping your crawl space fresh? Ask Improvi.ai for personalized guidance.