Start with what the census can actually tell us about your postal area, then add the dates only you know about your house.
For display only, an FSA is called primary era when one official 2021 Census construction band contains more than half of its occupied private dwellings. Otherwise HomeAge calls it mixed and shows the two largest bands. Statistics Canada does not publish a “primary era” category; this is only a transparent HomeAge shorthand for reading the map.
The census records the original construction period of dwellings in a postal FSA. It does not tell HomeAge the build year, renovations, materials, condition or maintenance history of a particular address. Material cards show documented era overlap only. Maintenance dates come from you.