Costs, Price Factors and 2026 Rules
Do you need a permit to replace a roof or siding in Canada?
Roofing and siding permit rules are set by each municipality. See how Toronto and Montreal treat re-roofing, when structural work triggers a permit and how to check yours.
Whether you need a permit to replace a roof in Canada depends on your municipality, because cities and towns administer the building code your province has adopted. As a broad pattern, replacing roofing material like for like with no structural work often does not need a building permit in many Ontario cities, while structural work (new rafters or trusses, changing the pitch, adding dormers, replacing large areas of deck structure, switching to a much heavier material) almost always does. Some cities go further: Montreal generally requires a permit to replace a roof covering, with borough-by-borough exceptions and material rules. Heritage districts can require approval for any visible change. Always check with your city's building department before work starts.
This guide is part of the roof replacement cost overview.
Why the rules differ
Each province adopts a building code, based in most cases on the National Building Code of Canada published by the National Research Council (Ontario, Quebec, British Columbia and Alberta publish their own editions or adoptions). The code sets technical requirements, and provincial legislation, such as Ontario's Building Code Act, lets municipalities issue permits and inspect work. Municipal bylaws then add zoning, heritage and sometimes material or appearance rules. The result is that the technical standard is similar across a province, but when a permit is needed varies city by city.
Two examples checked in October 2026
Toronto
The City of Toronto's guidance on when a building permit is required lists, among projects that do not need one, replacing existing roofing material provided no structural work is required. It also lists installing a skylight in a house of three storeys or less without a permit where no more than one rafter, joist or similar member (other than a truss) is removed, and re-cladding a house of three storeys or less with non-combustible material other than brick or stone veneer. Structural or material alterations need a permit. The city notes its lists are not exhaustive and that zoning bylaw compliance is required even when no permit is.
What this means in practice:
| Work in Toronto | Permit? (per city guidance) |
|---|---|
| Strip and re-shingle, no structural work | Not required |
| Replace rotten deck boards or plywood in places | Generally treated as repair; ask if extensive |
| New or larger dormer, pitch change, new rafters | Required |
| New skylight removing more than one rafter, or any truss | Required |
| New steel siding (non-combustible) | Not required for houses of three storeys or less |
| New vinyl siding (combustible) or stone veneer | Check with the city |
Montreal
The Ville de Montréal's guidance for sloped roofs says a permit is required to replace a sloped roof covering or change the structure of the roof, while repair and maintenance (such as repairing the covering or replacing a few shingles) does not need one. Several boroughs exempt replacing asphalt shingles with asphalt shingles, except on heritage buildings or in specially protected areas, and boroughs set their own material rules: some require reusing original covering materials, some prohibit certain materials, and Le Plateau-Mont-Royal requires a permit for slope or structure changes and for slate roofs or mansards.
For flat and low-slope roofs, a permit is generally required to replace the covering, and boroughs set solar reflectance (white roof) requirements. See flat roof replacement costs.
The city's pages listed fees of $9.80 per $1,000 of work, with a residential minimum, and typical documents such as a cost estimate, a certificate of location and a technical sheet for the materials.
Elsewhere: what to ask
For other municipalities, check the building department's "do I need a permit" page or call. Ask specifically:
- Is a permit needed to replace roofing material like for like?
- Does replacing the roof deck (sheathing) count as structural?
- Do I need a permit to change materials, for example asphalt to metal or slate?
- Is the property in a heritage district or subject to design guidelines?
- Is a permit needed for new siding, and does combustible siding near a property line need review?
- Are skylights, solar panels or new roof vents treated separately?
- Who must apply, the owner or the contractor, and what are the fees?
Heritage, condo and other approvals
- Heritage designation: properties designated under provincial heritage legislation, or in heritage conservation districts, may need heritage approval for changes to roofing material, colour or profile.
- Condominiums and co-ownerships: roofs and exterior walls are usually common elements. The condo board or syndicate decides and contracts the work.
- Homeowners' associations and covenants: some newer subdivisions restrict roofing colour or material through registered covenants.
- Airport or utility rules: rarely relevant for a re-roof, but cranes near airports or power lines need clearances.
Permits and the cost of your job
A permit adds direct and indirect costs: the fee, time for drawings if structural work is involved, inspections that can delay closing up the roof, and sometimes an engineer's letter for heavier materials. Ask contractors whether the price includes obtaining the permit and who will be present for inspections. Write it into the contract; see what a roofing contract should include.
Illustrative example: a $40,000 job in a city that charges an illustrative $10 per $1,000 of construction value would carry a $400 fee: $40,000 ÷ 1,000 × $10 = $400. Check your own municipality's fee schedule, which may use a different basis, such as floor area.
Permits and siding projects
Replacing siding often raises the same questions as roofing. In addition to the combustibility issue noted in Toronto's guidance, walls close to a property line have limiting distance requirements under the building code that can restrict combustible cladding and unprotected openings. Adding exterior insulation changes the wall assembly and may need review. See siding replacement costs.
FAQ
Does my roofer get the permit or do I?
Either can, depending on the municipality and the contract. The owner is ultimately responsible for complying with the building code and bylaws, so confirm in writing who applies and that the permit is posted before work starts.
Is a permit required for a roof repair after a storm?
Usually not for minor repairs or emergency tarping, but if structural members were damaged, a permit is likely required to rebuild them. Your insurer may also ask for proof that work was permitted.
Do I need a permit to add solar panels to my new roof?
Often yes, for structural and electrical review, but rules vary. Coordinate solar plans with the re-roof so the panels are not removed again in a few years.
Sources
- City of Toronto — "When do I need a building permit?" guidance
- Ville de Montréal — "Renovate a sloped roof" and "Renovate a flat roof or a low-sloped roof"
- National Research Council Canada — National Building Code of Canada
- Ontario e-Laws — Building Code Act, 1992 and the Ontario Building Code
- Régie du bâtiment du Québec — Quebec Construction Code and contractor rules
