The Building Application Status website provides access to information relating to the status of active building permit applications in the City of Toronto.
The information contained on this site is for active permits (permits that are not closed or canceled) that are less than five years old.
Search for Building Permit Status (Note: this application is best viewed using the latest version of Firefox)
You can also look to see if a permit card is posted on the site or you can go to your local district office and ask if that particular address had a permit issued for it.