mold under carpet 5

https://wiki-spirit.win/index.php/Essential_Steps_for_Water_Damage_Carpet_Drying_and_Mold_Prevention

That musty smell that just won't go away, even after a deep clean? It's probably mold under your carpet. I discovered it when I lifted a corner to move a bookshelf. The rubber backing was stained with black and green patches, and the padding felt damp and slimy. It’s gross, and honestly, it’s a health hazard too. Once you find it, you realize that musty smell was the mold’s way of telling you it was there all along.