In short
- Ottawa averages on HomeStars: about $7,200 for asphalt shingles, about $22,500 for metal, about $15,000 across all new roofs.
- One Ottawa firm prints $5,000 to $10,000 for an average shingle replacement and one to three days on site.
- Rotten decking is found only after the old roof is off, so the quote should name a price per sheet.
- Asphalt shingles are exempt from a City of Ottawa building permit; structural work and heritage properties are treated differently.
Typical prices in Ottawa
| Job | Typical range | Notes |
|---|---|---|
| Asphalt shingle roof | $4,000–$20,500 | HomeStars Ottawa; average about $7,200 |
| Metal roof | $7,500–$55,000+ | HomeStars Ottawa; average about $22,500 |
| New roof, all types | $8,000–$60,000+ | HomeStars Ottawa; average about $15,000 |
| Average shingle replacement | $5,000–$10,000 | One Ottawa firm’s published page |
| Tear-off and disposal | $1,000 and up | Canada-wide guide from an Ottawa firm, depends on roof size |
Sources. HomeStars, Roofing Cost Guide for Ottawa, updated 21.08.2026, seen 29.10.2026 (averages and lowest and highest reported jobs). Roofmaster, Roof Replacement in Ottawa, seen 29.10.2026 (one firm’s range, days on site, steps). JDM Roofing, Roof Replacement Cost in Canada, post of 15.08.2025, seen 29.10.2026 (tear-off line). Rules: Ontario, guide for home renovation and roofing businesses and City of Ottawa, projects not requiring building permits, both seen 29.10.2026. Custom Contracting, Roofing Cost Ontario, seen 29.10.2026 (one Ontario firm, November booking note).
Signs the roof has reached the end
One Ottawa roofer lists the pattern that points to replacement: shingles curling, cracking or lifting across whole slopes, granules turning up in the eavestroughs, several leaks or leaks that return after a patch, and a deck that feels soft or looks uneven from the ground. The same firm calls a roof younger than fifteen with damage in one place a repair job.
HomeStars adds constant leaks, a fallen tree or storm damage, and a repair bill above the price of a new roof. If your roof sits between the two cases, read repair or replace.
What the crew does on the job
A full replacement follows the same order on most Ottawa houses:
- Tear-off. The old roofing comes down to the deck. The pile is loaded into a bin or trailer.
- Deck inspection. With the deck bare, the crew checks for soft or wet boards and replaces them. This is the one part of the job that cannot be priced exactly in advance.
- Underlayment and ice protection. A waterproof membrane goes along the eaves and in the valleys. In Ottawa this layer fights ice dams, see ice dams.
- Ventilation check. Intake at the soffit and exhaust near the ridge need to move air. New shingles over a blocked attic repeat the old problems. The roof ventilation page explains the rules.
- Shingles or metal, and flashing. Every chimney, vent, skylight and valley gets fresh flashing.
- Cleanup. Nails are swept from lawn and driveway.
Most installs take one to three full days on an average house, according to one Ottawa firm. Ask what happens if rain arrives with the roof open.
Tear-off or overlay
New shingles can go on top of an old layer or on a stripped deck. HomeStars says the cost of an Ottawa roof changes a lot with the choice between a new layer over old shingles and a start from scratch. A tear-off adds removal and disposal, which a Canada-wide guide puts at $1,000 and up. An overlay leaves the deck unseen. Ask for both prices on the same quote.
What moves the price
HomeStars lists the drivers for Ottawa: tear-off or overlay, the pitch (the steeper, the dearer), damaged rafters or trusses, and a metal drip edge, which HomeStars recommends even though building codes leave it optional on a house. Add roof size, valleys, dormers, chimneys, skylights, material and bin access. The full table is on roofing cost in Ottawa, and a size-by-size view is on roof replacement cost. Shingles have their own page, asphalt shingle roofs, and metal is covered under metal roofing.
Rules before you sign
Ontario wants a written contract once work passes $50, listing the total, payment terms, start and finish dates and any sub-trades. The guide lets a final bill exceed the estimate by a tenth at most without your signature on a change, and gives you 10 days to back out of a contract signed at your own table. A deposit above 10% of the total runs against its advice. Re-shingling is on the City of Ottawa’s permit-exempt list, with exceptions set out on the roofing permits page.
Timing in Ottawa
HomeStars names spring as the preferred season for a new roof in Ottawa. One Ontario firm says most contractors stop booking new residential replacements in November. A roof leaking now is a repair-first case; see emergency roof repair.
Who you are dealing with
One independent Ottawa roofer gets your request, books the look and writes the quote. On the first call, ask whether the price assumes tear-off or overlay, and whether decking is priced per sheet.
Questions to ask the company
- Do you tear the roof down to the deck, or shingle over the old layer, and what does each cost?
- What do you charge per sheet if you find soft decking?
- Which underlayment and ice protection go on the eaves and in the valleys?
- Who orders and pays for the bin, and who sweeps the yard for nails at the end?
- Which days will you be on site, and how do you cover the open roof in rain?
Have this ready for the call
- The year the roof was last done, or the age of the house if you do not know
- Photos from the ground of every slope, the chimney and the eaves
- Leaks and stains inside, with the date you first saw them
- Where a bin can sit and where trucks can park
- Skylights, dormers, satellite dishes or solar panels the crew must work around
Questions people ask
How long does a roof replacement take in Ottawa?
One Ottawa firm says most installations take one to three full days. A bigger roof, slow material delivery, rain or surprises under the old shingles can stretch that. Ask the company which days it plans to work and how it protects the open deck if weather turns mid-job.
Is it better to tear off the old roof or shingle over it?
An overlay hides the deck from view. One Ottawa firm does not recommend it because it hides deck problems and shortens the life of the new roof. Ask for both prices on one quote, with the roofer’s reason for the option it prefers.
What happens if the crew finds rotten wood?
Soft or water-damaged decking is replaced once the roof is open, and nobody can price it exactly beforehand. One Ottawa firm says a contractor who promises otherwise is guessing. Get a price per sheet in writing. Under Ontario rules extra or different work needs a signed change to the contract before it goes on your bill.
Do I stay home during a roof replacement?
You can stay, and many households do. Expect noise and vibration on the top-floor ceilings. Move vehicles from the driveway, take pictures off top-floor walls and keep pets inside. Tell the company about a shift worker or a sleeping baby so the start time suits the household.
How do I know the roof is at the end of its life?
An Ottawa roofer points to curling or cracking shingles across whole slopes, granules in the eavestroughs, leaks that return after patching and a soft or uneven deck. Damage confined to one area of a younger roof usually means a repair. Ask the company which case yours is.