Updated July 2026
Roof Replacement & Repair Cost in the Cowichan Valley
Roof replacement in Duncan and the Cowichan Valley Regional District runs about $4 to $9 per square foot installed for asphalt shingles, $8 to $30 for metal, and $14 to $30 for cedar. On a typical home that works out to $8,000 to $20,000 for an asphalt re-roof and $18,000 to $45,000 or more for metal. Repairs commonly land between $500 and $3,000, moss treatment and roof cleaning between $300 and $1,200, and a documented roof assessment between $200 and $500. Roof size, pitch, number of existing layers, deck condition and access move every one of those figures, which is why an on-site assessment is what turns a range into a quote.
Updated July 2026
A roof cost range is a planning figure, not a price. It describes what comparable work has cost on comparable Cowichan Valley homes — it does not account for what is found once the existing roof comes off.
For a full breakdown of what the work involves, see roof replacement.
Roof replacement — planning ranges, Cowichan Valley (2026)
| Roof system | Installed cost per sq ft | Typical whole-roof range | Service life |
|---|---|---|---|
| Asphalt shingle | $4–$9 | $8,000–$20,000 | 15–30 years |
| Metal (panel & standing seam) | $8–$30 | $18,000–$45,000+ | 40–70 years |
| Cedar shake or shingle | $14–$30 | $28,000–$60,000 | 25–50 years |
| Flat / low-slope torch-on | $4–$12 | $8,000–$24,000 | 15–25 years |
What actually drives the number
Square footage is the starting point and rarely the deciding one. Pitch comes next: past about 6-in-12 the work needs staging and fall protection, and the day rate climbs with it. Then layers — a roof carrying two existing layers doubles the tear-off and the disposal.
Deck condition is the variable nobody can price from the ground. Sheathing under a long-running valley leak, or plywood delaminating on a shaded north slope, is discovered when the roof is opened. A good quote states an allowance for it rather than pretending it will not happen.
After that: the number of penetrations and valleys to flash, whether venting has to be built rather than replaced, and access for a disposal bin. On a rural property toward Sahtlam or Lake Cowichan, access alone can move a quote by four figures.
Asphalt versus metal over forty years
Compared on the day, metal loses badly — two to three times the asphalt figure. Compared over the life of a house, the arithmetic changes. Asphalt at 15 to 30 years means two re-roofs inside the span a single metal roof covers, and on the coast asphalt tends toward the lower half of its rated range because roofs stay wet from November through January.
Two asphalt re-roofs at today's $8,000 to $20,000 sit in the same territory as one metal roof at $18,000 to $45,000, before counting the moss treatment interval that asphalt needs and metal largely does not. That does not make metal correct everywhere. It makes metal a question worth asking on exposed, steep, or heavily treed roofs, and on houses the owner intends to keep.
Repairs, maintenance and assessment — Cowichan Valley (2026)
| Work | Typical range | What drives it |
|---|---|---|
| Roof leak & flashing repair | $500–$3,000 | Access, number of failure points, sheathing affected |
| Moss treatment & roof cleaning | $300–$1,200 | Roughly $0.20–$0.75 per sq ft; no pressure washing on asphalt |
| Gutter & valley clearing | $150–$400 | Roughly $0.70–$1.30 per linear foot; tree cover |
| Documented roof assessment | $200–$500 | Roof size and access; often credited against work that follows |
Planning ranges for Cowichan Valley homes as of July 2026, GST excluded. Labour on southern Vancouver Island runs roughly 15–20% above the provincial average. Figures are not a quote — an on-site assessment produces the actual number.
Repair, maintain, or replace
The test is remaining service life in the surrounding field, not the size of the problem. A failed chimney flashing on a twelve-year-old roof is a $500 to $3,000 repair. The same failure on a twenty-six-year-old roof with granule loss and curling edges is money spent immediately before spending it again.
Maintenance is the cheapest line in the table and the one that moves the others most. Moss treatment at $300 to $1,200 on a regular interval is what gets an asphalt roof to the top of its rated range instead of the bottom — and the difference between those two outcomes is a full replacement, brought forward by years.
Why two quotes on the same roof differ
Usually because they describe different work. One includes tear-off to the deck, new ice-and-water membrane at eaves and valleys, new flashing, and corrected venting. The other lays new shingles over the existing layer with reused flashing. Both say 'new roof'.
Read for the specifics: how many layers come off, what underlayment is specified, whether flashing is new or reused, whether venting is being brought to the BC Building Code minimum of 1/300 of the insulated ceiling area, what the sheathing allowance is, and whether disposal and cleanup are in the figure. A quote that names all seven can be compared. A single number cannot.
Also check whether the scope touches structure, which is where permit requirements start — the roofing permits guide sets out which Cowichan Valley authority applies.
Getting a figure you can budget from
An on-site assessment takes about an hour on a typical Duncan or North Cowichan home: the roof surface, the penetrations, the gutters and valleys, and the attic side where access allows. What comes back is a written scope naming the materials, the underlayment and venting, what is removed, what is allowed for sheathing, and a figure with the variables that could move it.
Nothing in the tables above replaces that. The ranges are there so a quote can be judged as reasonable or not before anyone signs it.
Compare system options on metal roofing, or, for an existing system, roof repair. Cowichan Roofing serves Duncan and North Cowichan.
Cowichan Valley roofs vary more than any table can capture — request a free quote and get the scope, the materials and the figure in writing after an on-site assessment.