Hamilton conditions that change how shingle replacement & roof replacement is done
If you mapped our Hamilton service calls on a calendar, you would see the same shape every year: the problems are created in February and paid for in November.
Post-war subdivisions across Halton share the same construction generation, so when one street starts showing the same defect, the neighbours usually follow within a couple of seasons.
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.
Across Mount Hope, Corktown, Strathcona, Inch Park and Twenty Place, 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 Bruce Trail, 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.