Markham conditions that change how chimney flashing repair is done
Homeowners in Markham tend to call us at one of two moments: the week before guests arrive, or the week after something started smelling wrong.
Post-war subdivisions across York share the same construction generation, so when one street starts showing the same defect, the neighbours usually follow within a couple of seasons.
Salt spray and road grit carried by winter wind accelerate corrosion on exterior metal components far faster in York than the manufacturer's rating assumes.
Across Markham Village, Cachet, Devil's Elbow, Vinegar Hill and Milliken, 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 Main Street Unionville, the practical takeaway is that a chimney flashing repair 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.

