The local factors behind chimney cleaning & sweep in Cobourg
The difference between a $200 service call and a $6,000 rebuild in Cobourg is usually about eighteen months of ignoring a small symptom.
Post-war subdivisions across Durham share the same construction generation, so when one street starts showing the same defect, the neighbours usually follow within a couple of seasons.
Salt spray and road grit carried by winter wind accelerate corrosion on exterior metal components far faster in Durham than the manufacturer's rating assumes.
Across Division Street, Ontario Street, Elgin Park, Legion Village and Downtown Cobourg, the housing stock changes street by street, and the correct method changes with it. A century home with a soft-brick stack does not get the same treatment as a 2010 build with a factory-built vent — using one method on both is how systems get damaged.
the practical takeaway is that a chimney cleaning & sweep visit should start with an assessment, not a tool. Any crew that begins work before telling you what they found is guessing on your behalf.

