A 1794 village, but a mid-century housing stock
Thornhill’s founding date and its housing stock are two different things, and conflating them leads to bad assumptions. The village genuinely dates to 1794, with a grist mill and sawmill on the Don by 1802 and Benjamin Thorne arriving in 1820 to run the mills and tannery that gave the place its name. But the protected heritage core is tiny: the Vaughan-side conservation district covers eighty-two properties, and the Markham-side district, designated in 1986, was Markham’s first. The overwhelming majority of Thornhill housing is the suburban ring built from the 1960s through the 1990s, which is squarely the nailed-subfloor era and now thirty to sixty years old. Worth excluding: Thornhill Woods is Vaughan’s Block 11, whose block plan only reached committee in 2003, making it far too new for age-related squeaks.