Shed Permit Guide in Niagara Region, Ontario

Here is the shed permit question, in order. Step 1: check the footprint against 15 m2 (about 161.5 sq ft). Ontario's shed exemption is a specific, five-condition test -- Ontario Building Code, Division C, Article 1.3.1.1.(6) -- quoted here verbatim, since almost nothing else online cites the actual article: a shed is exempt from the permit requirement only if it (a) is not more than 15 m2 in gross area, (b) is not more than one storey in building height, (c) is not attached to a building or any other structure, (d) is used only for storage purposes ancillary to a principal building on the lot, and (e) does not have plumbing. At more than 15 m2, a building permit is required, no matter the other four conditions. This article lives in the CURRENT Building Code, adopted by O. Reg. 163/24 s.1: the National Building Code of Canada 2020, as amended by "Ontario Amendments to the National Building Code of Canada 2020" -- currently the edition dated July 17, 2026, put there by O. Reg. 242/26. The predecessor regulation, O. Reg. 332/12, was revoked January 1, 2025, but this exemption's text carried over unchanged, at the same article number, into the current edition. One correction to how this is sometimes summarized elsewhere: condition (e) is plumbing ONLY -- hard-wired electrical is NOT part of this exemption test. Adding electrical does not, by itself, remove the building-permit exemption, but it does trigger its own separate approval through the Electrical Safety Authority, a different process from this permit exemption. Step 2: check the other four conditions. A shed under 15 m2 that is two storeys, attached to the house or another structure, or used for anything beyond storage, or fitted with plumbing, is not exempt just because it is small. Step 3: run the worked examples against your own plan. A 10x10 shed (100 sq ft) and a 12x12 shed (144 sq ft, about 13.4 m2) both fall under the 15 m2 threshold and are usually exempt if the other four conditions hold. A 10x12 shed (120 sq ft, 11.15 m2) also falls under the 15 m2 threshold -- this is the exact size where the shed-vs-not-shed line first matters: as a storage-only shed it is exempt (subject to the other four conditions), but if that identical 11.15 m2 footprint were used for anything other than storage -- a gazebo, a bunkie, a small workshop -- it would fail condition (d), lose the shed exemption entirely, and fall back to the Building Code Act's own 10 m2 definition of a "building," which it exceeds. Same footprint, opposite answer, depending on use. A shed sized 16x16 (256 sq ft, well over 15 m2) or larger needs a permit outright. Step 4: check zoning setbacks, height rules, AND cumulative lot coverage -- even if you are permit-exempt. Being under 15 m2 exempts you from the building-permit requirement, not from these three separate zoning tests, and none of them are answered by the 15 m2 shed test above. Here are the real numbers, not just a "check with your municipality" deferral. In Niagara Falls, Zoning By-law 79-200, s.4.13, sets an accessory-structure setback of 0.45 m from any lot line in a rear yard, 1.2 m from an interior side lot line, and 4.5 m from the side lot line on a corner lot, plus a maximum height of 3 m to the walls or supporting posts (4.6 m to the peak of a pitched roof). In St. Catharines, By-law 2013-283, s.2.1, sets 0.6 m from an interior side or rear lot line for a structure 4.5 m tall or under (1.2 m if taller), and a maximum height of 4.5 m to the walls (6 m to the peak). In Niagara-on-the-Lake, By-law 4316-09, s.6.1, sets 1.2 m from the main building and a maximum height of 6 m to the peak. None of the three towns generally allows an accessory building in a front yard. And there is a THIRD test beyond setback and height, one this page has never named until now: all three towns cap how much of the WHOLE lot every accessory building and structure combined -- not just this shed -- may cover. Niagara Falls: 15% of the lot area or 93 m2, whichever is lesser (s.4.13(g)). St. Catharines: 10% of the total lot area, excluding in-ground pools (s.2.1(c)). Niagara-on-the-Lake: 8% of the lot area, for lands inside its urban boundary only -- Virgil, Old Town, Queenston, St. Davids, and Glendale (s.6.1(a)(1)); rural NOTL uses a different by-law this page does not cite a figure from. That cumulative cap is the honest answer to a different, more common question than "is this one shed under 15 m2": there is usually no fixed COUNT limit on how many sheds a property may have, but there is very much a coverage limit, and an existing garage or shed already on the lot counts against the same cap a new one would use up. See /permit-guide/ for the same figures in the site's full per-municipality context. Step 5: confirm with your own municipality before you build. Niagara Falls, St. Catharines, and Niagara-on-the-Lake each administer their own building department and process, so the exempt-or-not answer above is the Ontario-wide starting point, not a substitute for checking locally.