Do You Need a Permit for Commercial Demolition in Ontario?

Short answer: almost always, yes. If you're taking down a commercial building — or even part of one — in Ontario, you need a demolition permit from your local municipality before anyone swings a hammer. Here's how it actually works, and where owners get tripped up.

The legal baseline

Under Section 8 of Ontario's Building Code Act, no one can demolish a building without a permit issued by the municipality's chief building official. The exemptions are narrow — certain farm buildings and very small structures under the Building Code. If it's a commercial property in Toronto, Mississauga, or anywhere else in the GTA, assume a permit is required.

Demolition permit vs. interior alteration permit

This is the distinction that confuses most owners:

A demolition permit applies when you're reducing the building's footprint — removing a whole building, a wing, or exterior walls.

An interior alteration permit covers gut-outs and strip-outs where the shell stays intact. Tearing out partitions, ceilings, flooring and mechanical systems inside an existing commercial unit is typically permitted as an alteration, not a demolition.

Either way, you're dealing with the building department. Which permit you need changes the drawings, review process and timeline — so figure it out before you schedule crews.

Before the permit: the designated substances survey

Here's the step that stalls more demolition projects than the permit itself. Under Section 30 of Ontario's Occupational Health and Safety Act, the building owner must have a designated substances report prepared before contracting demolition or renovation work — and provide it to every contractor bidding the job before they sign a contract.

That survey identifies asbestos, lead, silica, mercury and other designated substances in the building. Municipalities like Brampton now require it as part of the commercial demolition permit package. No survey, no permit, no start.

If the survey finds asbestos — common in commercial buildings, especially pre-1990 stock — abatement has to be handled under Ontario Regulation 278/05 before or during demolition. Higher-risk Type 2 and Type 3 asbestos operations also require advance notice to the Ministry of Labour, Immigration, Training and Skills Development. These notifications are not optional, and skipping them means stop-work orders and fines that cost far more than doing it right.

What Toronto adds on top

In Toronto, demolition permit applications go through Toronto Building with full plans, a site plan referenced to an up-to-date survey, and applicable law clearances. For larger or complex structures, the city also wants the structural design characteristics, a demolition method and schedule, and confirmation that a professional engineer has been retained to review the demolition.

One thing commercial owners don't usually face: Toronto's demolition control regime is aimed primarily at residential rental housing. Commercial and industrial demolitions generally proceed under the standard demolition permit and planning approvals.

Realistic sequence for a compliant demolition

1. Designated substances survey (owner's responsibility, before tendering)
2. Abatement scope defined, if hazardous materials are found
3. Permit application with drawings, site survey and required clearances
4. MLITSD notification for Type 2/3 asbestos work, where applicable
5. Abatement with clearances, then demolition
6. Inspections and sign-off

Get the order wrong — say, tendering demolition before the survey exists — and you'll re-tender once the asbestos shows up, usually at a worse price and a later date.

Who handles all this?

A demolition contractor worth hiring manages the permit applications, drawings and inspection coordination as part of the contract, and self-performs or directly manages the abatement so there's one accountable party from survey to sign-off. That's how Sofisa runs every demolition project across Toronto and the GTA — permits, abatement to O. Reg. 278/05, demolition and haul-off under one contract.