I've discovered some mold and damage on my baseboards after moving a bookcase in my home, and I'm trying to figure out if this is due to condensation and lack of ventilation, or if it looks like there's water intrusion from somewhere. My house was built in 1942 and has original cedar shingles. There isn't any plumbing nearby, so I don't think it's a pipe problem. I've checked for foundation cracks and there seem to be none. The walls are made of plaster with no insulation in the floors or walls, and we use a heat pump and mini splits for climate control. I'm open to tackling a DIY solution but could really use some guidance on where to begin. Is this something that requires tearing down affected walls? Any advice would be appreciated!
2 Answers
It could also be a case of no airflow combined with high humidity behind the bookcase that's causing the mold. A good first step would be to clean the affected area, keep it free from furniture, and monitor if the mold comes back afterwards.
Based on the condition of your baseboards, it sounds like you might be dealing with water coming in from outside. Is this damage happening on the main floor? You should check what’s directly outside that area—like the grading and if there's any pooling near the foundation. Also, what type of foundation do you have?