Helpful resources that should introduce residents of historic properties to the joys of finding out when their homes were built.

SEMCOG Building Age Map

The map provides comprehensive information about when many Metro Detroit structures were built. Dates are available for many Downriver buildings. Unfortunately, nearly all buildings in Rockwood and Grosse Ile have no information and nearly all houses in Southgate and Wyandotte give a "0" for the year built.

"Downriver Year Built" .kmz file

CURRENT VERSION: 1 (mainly commercial buildings so far)

Composed by the founder of the Downriver Wiki, this includes buildings in Grosse Ile, Rockwood, Southgate and Wyandotte, intended to provide more complete coverage than the SEMCOG map. Sourced from personal knowledge, the former Google Earth Pro parcel layer and sources linked to on this article. The oldest buildings, constructed in the 19th century, are in brown, and each decade (every 20 years beginning in 1940) continues further through the rainbow palette, ending with buildings built in the current millennium in purple.

Place Promo

This site fills in many gaps in Wyandotte building dates that are left by the SEMCOG map. An added bonus is that 1970s photographs and detailed information are provided for most listings. Unfortunately, the search function broke back sometime in 2014, making things difficult.

When navigating to other portions of that site, you will notice that they have additional information on historic Wyandotte properties.


One of the more major real-estate-listing websites also provides building dates for many Downriver homes, including those ignored by the above sources.

Polk Directory

Sanborn Maps