How can I tell if water damage in an unfinished attic is new?

Question

How do I tell if water damage in an unfinished attic is new or old? House is 77 years old.

Answer 1

1. Check for residual moisture. Feel whether it's damp or cool, or use a moisture meter.

2. Check for fresh mold or mildew. Does anything rub off? Does it have a strong odor?

3. Inspect for dust, insect evidence, and other debris. Obviously older damage will not be clean on the surface.

4. Set up a test. Something like paper towel secured in position will make it very clear whether it's been wet since installation due to deformity and staining.