Why roof moss & algae treatment works differently in Pickering
Nearly every urgent roof moss & algae treatment call we take in Pickering began as something a homeowner noticed months earlier and reasonably decided to watch.
The swing between a January cold snap and a February thaw can move a masonry assembly enough to open joints that looked sound in the fall.
Older Pickering stock was built when soft lime mortar and clay liners were the standard; modern high-efficiency appliances vent very differently, and the mismatch causes condensation the original builder never planned for.
Across Village East, Bay Ridges, Woodlands, Greenwood and Duffin Heights, 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.

