Start with conditions, not a product
Staining on rafters or sheathing is a symptom you can see, not a diagnosis. The real work is tracing the water back to where it's entering the roof or attic, tracking humidity, judging how far it has spread into framing and insulation, containing the space properly, and verifying the result afterward.
Build a complete scope
- The moisture source, established before any cleaning is quoted
- Whether uphill groundwater or attic ventilation is driving it
- How the work area is contained, harder in open early-1900s framing
- What is removed versus cleaned, and the basis for that decision
- Verification afterward, plus the drainage or venting fix that prevents a repeat
Asheville context
A lot of Asheville's bungalow and Craftsman-era housing has shallow, low-pitched attic spaces with minimal ventilation by modern standards, and valley fog that lingers through mountain mornings keeps ambient humidity high enough that marginal attic airflow can turn into a persistent moisture problem rather than an occasional one.