[EADGBE]

Though much older homes do exist, in the US (they're using a "$" in their comment) 50 years +/- 10 years is pretty commonly the average age for a "mature" house where most of the cities the homes are in weren't established until the mid-to-late 1800's. Especially for the suburbs, which are about the age of these homes.

I grew up in a home built in 1954. It didn't survive a World War, but it's had its fair share of powerful tornadoes, blizzards, and the like and has been relatively unscathed since its inception (minus a new sewer line). With timber framing!