Mold and mildew are the things in basements that actually cause the musty odors, but moisture is the underlying issue that causes mold and mildew growth. Addressing moisture and water problems and then removing materials that are moldy are some of the best ways to get rid of the musty odors. Preventive measures after that—like installing air fresheners and a dehumidifier—can help keep musty odors from returning.

To maintain an outdoor structure, perform regular inspections for damage, leaks, and weak joints. Clean the structure regularly, treat or repaint wood surfaces for weather resistance, and reinforce any weak joints to prevent deterioration and ensure its longevity.

The first step to preventing foundation cracks is to repair any current ones. When one crack forms, it becomes more likely that a second crack will follow. A few other tips include performing regular foundation checks, cleaning spouts and gutters, and installing exterior drains if needed. For those living in a hot and arid area, you should water your foundation every other day.

Underfloor insulation alone will not cause moisture and mold, but improper installation can. Although the purpose is to seal any drafts, your subfloor still needs ventilation. If you seal the area too tightly and prevent all airflow, this can cause moisture to get trapped. This moisture eventually leads to mold and—if your floors are wood—rotting.