The official website of the City of London300 Dufferin Avenue519-661-CITY (2489)3-1-1 (within London)

Finishing the Basement

This information is intended to give you an idea of what types of basement renovations and/or finishes require a building permit.  If you have any questions please contact the City of London to clarify and confirm the details of your project.

For more detailed information the City of London has designed the 'Homeowner's Guide to Building Permits' to help you answer some general questions before applying for your permit.  The Ontario Building Code has even greater detail about what the minimum standards are for safe construction.


The following activities REQUIRE A PERMIT from the City of London:

  • Insulating;
  • Adding fixtures to the rough-ins;
  • Roughing in plumbing;
  • Changing the uses of the room(s);
  • Moving/altering walls and/or openings;
  • Windows & Doors: creating them, changing them, enlarging or altering them;
  • Stairs; moving, changing, rebuilding, and;
  • Foundation: Anything that cuts, alters or involves the foundation

Don't forget: adding any finished area to your basement will require a City of London Building Permit. 

Please Note: This list does not include electrical work, which may require a permit from the Electrical Safety Authority (ESA) and is not issued by the City of London.  The ESA has resources to help you contact a local professional electrician.


Last modified: