The local factors behind roof moss & algae treatment 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.
Range hoods and basement bathroom fans routinely out-pull an older flue, so the house depressurises and the flue reverses — a Cobourg problem that looks like a chimney fault but starts elsewhere in the building.
Wind loading off Lake Ontario pushes driving rain against the south and west faces of a house, which is why water entry so often shows up on one side of a Cobourg home and nowhere else.
Across Northam, New Amherst, Ontario Street, Division Street and Cobourg Beach, 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 roof moss & algae treatment 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.

