Rochester averages 100 to 110 inches of snow from Lake Ontario lake-effect systems and logs fewer than 100 sunny days per year. Severe freeze-thaw cycling creates ice dams that force meltwater under shingles into attic insulation and wall cavities—the most common attic mold source in Rochester homes. Spring thaw drives basement moisture above 80% RH for weeks.
Ice dam attic mold and basement mold from snowmelt seepage are Rochester's dominant loss types. Pre-1950 North End homes—many with original plaster walls and minimal vapor barriers—have persistent hidden moisture pathways. Genesee River and Irondequoit Creek flooding has also affected the Genesee-Jefferson corridor.
New York Labor Law Article 32 requires licensed mold assessors and abatement contractors for projects over 10 square feet. Verify your contractor holds a current New York State DOL Mold Contractor license and commits to independent third-party clearance testing—both are state law requirements. Call 24/7 to begin within 48 hours.