Markham conditions that change how roof leak repair is done
Most Markham homeowners book roof leak repair for one reason and discover a second problem on the same visit.
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.
Older Markham 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 German Mills, Rouge Fairways, Berczy Village, Old Markham Village and Victoria Square, 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 roof leak 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.

