Why shingle replacement & roof replacement works differently in Waterloo
Waterloo sits in a freeze-thaw belt, and freeze-thaw is what quietly takes apart masonry, flashing and venting.
Salt spray and road grit carried by winter wind accelerate corrosion on exterior metal components far faster in Halton than the manufacturer's rating assumes.
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 Waterloo home and nowhere else.
Across Amos, Lakeshore, Empire, Eastbridge and MacGregor, 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.
If you live anywhere near the University of Waterloo, the practical takeaway is that a shingle replacement & roof replacement 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.