Always a permit
- New buildings over 10 square metres (about 108 sq ft), which catches most sheds, garages and workshops
- Additions of any size attached to the house
- Structural work: removing or cutting load-bearing walls, adding beams or lintels, altering floor or roof framing, underpinning
- New or altered plumbing, including a basement bathroom rough-in
- Material HVAC changes: new ductwork systems, wood stoves, fireplace inserts
- Change of use, including every legal basement apartment (details in what makes a Brantford suite legal)
- Foundations, excavation and new window or door openings cut into structural walls
- Septic system installation or alteration
- Decks above prescribed heights or attached to the dwelling (thresholds vary by municipality)
Usually exempt
- Painting, flooring, trim and tile
- Cabinet and countertop replacement with no plumbing moves
- Like-for-like fixture swaps (toilet for toilet, sink for sink, same location)
- Shingle replacement on the same structure
- Small detached sheds under 10 square metres (zoning still applies)
- Fences (by-law territory, not Building Code, pool enclosures excepted)
"The surprises that catch homeowners are always the same three: the shed that's 12 square metres instead of 10, the 'just a rough-in' bathroom that's legally new plumbing, and the pass-through cut into what turned out to be a bearing wall. When in doubt, one phone call to the building department settles it for free. I make that call weekly."
Mitch Fraser, owner, Ontario Contracting Co.
The two rules that resolve every edge case
Rule 1: the Chief Building Official has the final say. Exemption lists are guidance; your municipality's interpretation is law. Rule 2: electrical is separate. Building permits don't cover electrical work, which runs through ESA notifications by a Licensed Electrical Contractor regardless of whether a building permit exists.
Where to actually apply depends on your address: Brantford applies online through its Cloudpermit portal, while the County of Brant still runs a submitted-package system. What skipping it costs is documented in the no-permit consequences article.