Roof installation
Asphalt and metal roof installation in Nanaimo, tear-off to final sweep
Nanaimo Roofers installs new asphalt shingle and metal roofs across Nanaimo, Lantzville, Cedar and Gabriola Island. We tear off to the deck every time, so we find and replace soft or rotten sheathing before any underlay goes down. Asphalt shingles need a slope of at least 1 in 3, and we measure yours before we quote.
We build a new roof in sequence, and most of what decides how long it lasts gets done before we fasten the first shingle.
What a tear-off exposes
Stripping to the deck is the only way we can see the sheathing. We cut out and replace panels that have gone soft under a leak, and we check the fasteners holding the rest. Underlay goes on next: asphalt-saturated sheathing paper or No. 15 felt, with head and end laps of not less than 50 mm, overlapping the eave protection by at least 100 mm. None of it is visible once the roof is on.
The slope decides the material
Every roof covering has a minimum slope. Asphalt shingles need 1 in 3, or 1 in 6 where we use the low-slope method. Profiled metal starts at 1 in 4 and has no upper limit. Modified bituminous membrane runs from 1 in 50 up to 1 in 4. The floor across the whole table is 1 in 50. We measure the slope first, so your quote does not change halfway through the job.
How much eave protection do we install?
We run eave protection 900 mm up the slope, carried to a line 300 mm inside the inner face of the exterior wall. On a shallow pitch, a north slope, or an eave that has already backed up once, we carry it further than that.
How much venting we put in
We vent to at least 1/300 of the insulated ceiling area, and 1/150 below a 1-in-6 slope or where the roof is framed with roof joists. We split that area across opposite sides, with at least 25% at the top and at least 25% at the bottom. A roof vented only at the ridge has nowhere to draw air from, and we check for that on every installation.
What it comes to
Our cost guide has the price and lifespan for each covering. The spread inside each range is the roof itself: dormers, valleys, penetrations, a second storey, and how much sheathing turns out to need replacing.
What's included
Asphalt shingle roof replacement
Standing seam metal installation
Roof deck and sheathing replacement
Attic ventilation correction
People also ask
How long does a re-roof take?
Most single-family roofs are a one to three day job once the crew is on site. A cut-up roof with several valleys, or one that needs sheathing replaced over a large area, runs longer. We name the expected number of days in the scope before we book the work.
Can a new roof go over the old one?
No. We strip every roof to the sheathing, because the deck is where failures start and layering would hide it from us. That way the underlay, the eave detail and the fasteners all land on sound material.
What happens if the sheathing is rotten?
We put a per-sheet rate in the quote and agree it with you before the tear-off starts. Nothing about the price changes on the day except the count of sheets we actually replace.
Does the old roof get hauled away?
Yes. We bring a bin in before the tear-off and it leaves with the old material.
Keep exploring
- What a new roof costsInstalled price by material, and what moves it on a given roof.
- Permits by communityWho issues the permit for an address, and what each authority asks for.
- Where the work isThe communities covered across the Regional District of Nanaimo.
- Metal roof systemsStanding seam and profiled metal from a slope of 1 in 4 with no upper limit, detailed for a 2.1 kPa ground snow load and a 0.50 kPa design wind.
- Roof repair and leak tracingFlashing, valleys, penetrations and laps. Finding where water enters a roof, which is almost never directly above the stain on the ceiling.
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