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Commercial Roofing FAQs

Straight answers to the questions London building owners and property managers ask us most.

How much does a commercial roof replacement cost in London?

It's priced per square foot and depends on the system, roof size, whether we tear off or recover, insulation, and roof access. There's no honest one-size number — that's why we do a free assessment and give you a written, itemized quote.

Should I repair or replace my roof?

If the membrane is sound and the issue is localized, we repair. If you're repairing the same spot repeatedly, the roof is near end-of-life, or the insulation is wet, a replacement is cheaper long-term.

TPO or EPDM — which is better?

TPO is reflective and lowers cooling costs; EPDM is a proven rubber membrane that excels in cold. It depends on your building — see our TPO & EPDM page.

Do you offer emergency roof repair?

Yes — 24/7 emergency response for active leaks, storm damage, and snow load across London and Middlesex County.

Are you insured, and is there a warranty?

Fully insured, WSIB-compliant, IHSA safety protocols. Installs carry manufacturer material warranties plus our workmanship warranty.

How long does a replacement take?

A few days to a couple of weeks depending on size, system, and weather. Large facilities are phased to keep you operating.

London, Ontario roofing questions

The things homeowners and building owners here ask us about our climate, the building code, and getting a roof through a Southwestern Ontario winter.

Do I need a permit to replace my roof in London, Ontario?

Like-for-like re-roofing — replacing shingles or membrane without structural changes — generally doesn't require a permit from the City of London. Structural work, replacing the roof deck or sheathing, or altering the roof usually does. Always confirm with the City of London Building Division before work starts.

How do I prevent ice dams on a London home in winter?

Ice dams form when heat escaping into the attic melts roof snow, which then refreezes at the cold eaves and backs water up under the shingles. You prevent them with proper attic insulation, balanced ventilation, and ice-and-water shield at the eaves — the details a correctly built London roof includes.

How long does a roof last in London's climate?

Architectural asphalt shingles typically last 20–30 years, but London's freeze-thaw cycling and wide temperature swings shorten that if the attic is poorly ventilated. Metal roofs commonly last 40–50+ years. Good ventilation is the single biggest factor in how long a roof lasts here.

Is ice & water shield required by code in Ontario?

Yes. The Ontario Building Code requires eaves protection such as ice-and-water shield in cold, ice-dam-prone climates like London. We install it as standard at the eaves and valleys.

How much roof ventilation do I need?

The Ontario Building Code calls for roughly one square foot of net free vent area for every 300 square feet of insulated attic — the 1-in-300 rule — balanced between intake at the soffits and exhaust near the ridge. Under-venting is a leading cause of attic condensation and ice dams in London.

Why does my flat roof pond with water after it rains?

A properly draining flat roof clears standing water within about 48 hours. Persistent ponding points to a drainage, slope, or clogged-drain problem, and standing water accelerates membrane and seam failure. Worth addressing before it turns into an interior leak.

When is the best time of year to replace a roof in London?

Spring through fall is ideal, when temperatures let shingles and membranes seal properly. We install year-round when needed and handle winter emergencies, but planned replacements are best scheduled in the warmer months.

Does home insurance cover roof storm or ice damage?

Sudden storm, wind, and ice damage is often covered; gradual wear, age, or neglect usually isn't. Photograph the damage inside and out and call us for a documented assessment to support your claim.

Still have questions? Get a Free Assessment

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