Why roof cleaning works differently in Port Hope
Port Hope sits in a freeze-thaw belt, and freeze-thaw is what quietly takes apart masonry, flashing and venting.
Older Port Hope 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.
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 Port Hope home and nowhere else.
Across Old Port Hope, Canton, Toronto Road, Elizabethville and Ganaraska, 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 cleaning 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.

