Commercial Roof Leak Insurance: What Ontario Policies Cover
What commercial roof leak insurance usually pays for, what Ontario's Insurance Act asks of you after a leak, and how to document the claim.
Call 1-833-775-7663 Oakville head office · Leak repairs, inspections and documentation for commercial flat roofs across Ontario
Karol Rajkowski
Vice President, OYH Roofing
Published October 5, 2026 · 8 min read
Short answer
Commercial roof leak insurance in Ontario usually covers sudden, accidental damage, such as wind tearing a membrane or a branch puncturing it, and the water damage that follows inside. It usually does not pay to fix a roof that leaked because of age, wear or poor maintenance. Your policy wording decides, so report the leak fast and document everything.
Does insurance cover a commercial roof leak?
Often, but only for the right cause. The Insurance Bureau of Canada puts the rule simply: insurance is meant to cover sudden and accidental loss or damage. A storm that tears off flashing is sudden. A membrane that wore out over many years is not. That is why every roof leak claim turns on the cause, and why the roofer's report matters as much as the photos.
| Cause of the leak | Usually covered? | Why |
|---|---|---|
| Wind tears off membrane, flashing or a hatch | Often | Sudden, accidental storm damage |
| Hail or a falling branch punctures the roof | Often | Sudden impact from outside |
| Ice dam suddenly backs water inside | Often, if sudden | Repeated ice damage counts as a maintenance issue |
| Water damage inside from a covered event | Often | The resulting damage is usually the covered part |
| Membrane worn out from age | Usually not | Wear and tear is expected, not accidental |
| Blocked drains and ponding from missed maintenance | Usually not | Lack of maintenance is not insurable |
| Slow leak that went on for months | Usually not | Gradual, ongoing damage is not sudden |
Roof leak insurance varies, so treat these as general patterns, not promises. Policies differ, and some add or remove coverage for specific causes. Read the exclusions page and call your broker before you assume either way.

Is the roof repair covered, or only the water damage inside?
Often only the water damage inside. The Insurance Bureau of Canada notes that water entering through a roof leak is typically covered on a home policy, but the roof damage itself is not when it comes from wear and tear or poor maintenance. Commercial property policies usually follow the same sudden-and-accidental rule, so a roof leak insurance claim can get two answers: one for the ceilings, stock and equipment, and one for the roof.
If wind or hail damaged the roof, the repair itself may be covered too. If the roof simply reached the end of its life, the repair or replacement stays the owner's cost, even when the damage inside is paid. Our warehouse roof replacement guide covers how to plan that work.
Which type of commercial property policy do you have?
Check the declarations page first. The Insurance Bureau of Canada describes two kinds of commercial property policy, and they treat a roof leak differently. Business interruption is a separate, optional add-on.
| Policy or add-on | How it works | What it means after a roof leak |
|---|---|---|
| Named perils | Covers only losses caused by the perils listed in the policy, subject to exclusions | The leak must trace back to a listed peril, such as wind or hail |
| All risk | Covers loss or damage from any peril unless it is specifically excluded | Broader coverage, so the exclusions page decides |
| Business interruption (optional add-on) | Covers lost income when a covered peril shuts the business down for repairs | Applies only if you bought it and the leak came from a covered peril |
For roof leak insurance, look first for the wording on wear and tear, deterioration and maintenance. That is where most of the answer sits.
What does Ontario's Insurance Act ask of you after a roof leak?
If your property policy covers fire, Ontario's Insurance Act makes a set of Statutory Conditions part of it, printed under that heading in the policy. Three of them shape every roof leak insurance claim: prompt written notice, reasonable steps to prevent further damage, and the insurer's right to inspect.
| Condition | What it says | What it means on a roof leak |
|---|---|---|
| 6. Requirements after loss | Give the insurer written notice forthwith, then a proof of loss as soon as practicable, stating when and how the loss happened | Call your broker or insurer the same day and follow up in writing |
| 9. Salvage | Take all reasonable steps to prevent further damage; the insurer contributes proportionately to reasonable costs | Have a roofer make a temporary repair and keep the invoice |
| 10. Entry, control, abandonment | The insurer has a right of access to survey and examine the damaged property | Keep damaged materials and photos, and ask before permanent repairs |
Condition 9 puts the duty to limit the damage on you, so a quick temporary repair protects both the building and the claim.
How do you file a roof leak insurance claim?
Follow the same order every time, and keep everyone off the roof except the roofing crew:
- Make the inside safe. Move stock and equipment, contain the water and keep people away from wet floors.
- Call your broker or insurer. Report the damage as soon as possible. According to the Insurance Bureau of Canada, most insurers run a 24-hour claims line.
- Book a temporary repair. The Insurance Bureau of Canada says policyholders must protect property from further damage if it is safe to do so, for example with tarps over a damaged roof, and should hire a professional when it is not safe.
- Document everything. Dated photos and video, a list of damaged items, notes, and every receipt.
- Get the cause in writing. Ask the roofer for a short report with photos that says what let the water in.
- Meet the adjuster. Show the damage and the report, and agree on permanent repairs before they start.
| Document | Why it matters |
|---|---|
| Dated photos and video of the leak and the damage inside | Shows what happened and when |
| Roofer's written cause-of-leak report | Separates sudden damage from wear and tear |
| Invoices for temporary repairs and cleanup | The insurer contributes to reasonable costs of preventing further damage |
| Inspection and maintenance records | Shows the roof was looked after |
| Policy declarations, exclusions and statutory conditions | Tells you what the policy covers and what it asks of you |
| Log of calls, names and the claim number | Keeps the claim on track |
Need a cause-of-leak report for your roof leak claim?
Call us after you call your insurer. We will inspect the roof, make a temporary repair where it is needed and document what we find.
Call 1-833-775-7663Request an assessmentWhat can you do if a roof leak insurance claim is denied?
Ask for the reason in writing and compare it with your policy wording. If you still disagree, the Insurance Bureau of Canada lists the next steps: the insurer's claims manager, then its internal ombudsman, then the General Insurance OmbudService (GIO). If the denial rests on the cause of the leak, a second roofer's report can help your roof leak claim.
| Step | Who | What to bring |
|---|---|---|
| 1 | Your adjuster, then the claims manager | The denial reason, the roofer's report and photos |
| 2 | The insurer's internal ombudsman | Ask for its final position letter |
| 3 | General Insurance OmbudService (GIO), 1-877-225-0446 | The final position letter. GIO's help is free and independent for home, auto and business insurance disputes. |
For general questions about how insurance works, the Insurance Bureau of Canada's Consumer Information Centre answers at 1-844-227-5422.
How do maintenance records protect a roof leak claim?
In a roof leak claim, maintenance records are your proof that the leak was sudden, not neglect. The Insurance Bureau of Canada says insurance covers unexpected and accidental events, not ones that result from a lack of maintenance. NRCA recommends inspecting roofs and making repairs twice a year, and most roof warranties also require the roof to be properly maintained.
Our guide on how to prepare a flat roof for winter lists the fall checks. The leak repair pages for Toronto and Mississauga explain what happens on a leak call.

Frequently asked questions
Will insurance cover a 20 year old roof in Ontario?
It depends on the policy, not just the age. Damage from a sudden event, such as wind or hail, can still be covered on an older roof, but wear from age is not. Some policies settle older roofs at actual cash value, often the cost to repair or replace less depreciation, as the Insurance Bureau of Canada defines it. Ask your broker how yours works.
What happens if a roof leak is left untreated?
The damage spreads. Water soaks the insulation under the membrane, stains ceilings, ruins stock and equipment, and can freeze and widen gaps in winter. It also weakens a roof leak insurance claim, because Ontario's statutory conditions require the insured to take reasonable steps to prevent further damage, and slow, ongoing leaks are usually treated as maintenance.
Does home insurance cover roof leaks?
Usually for sudden damage. The Insurance Bureau of Canada says home policies typically cover water damage inside from a roof leak, but not the roof itself if the damage comes from wear and tear or poor maintenance. Commercial property policies usually follow the same sudden-and-accidental rule, with their own wording and exclusions.
Are flat roofs more likely to leak?
Not when they are built and maintained well, but they depend on drainage. A flat or low-slope roof has to move water to its drains, and NRCA's test for proper drainage is no ponding water 48 hours after rain. Blocked drains, open seams and worn flashings are the usual trouble spots, which is why spring and fall inspections matter.
Does business interruption insurance cover a roof leak?
Only in some cases. Business interruption is an optional add-on to a commercial property policy, and it covers lost income when a covered peril forces the business to close for repairs, according to the Insurance Bureau of Canada. A leak from wind damage might qualify; a leak from a worn-out roof usually would not.
Should I make temporary repairs before the adjuster comes?
Yes, if they stop further damage. Ontario's statutory conditions require the insured to take all reasonable steps to prevent further damage, and the insurer contributes proportionately to reasonable costs. Have a roofer do the work rather than building staff, photograph everything first, keep the invoice for the roof leak claim, and agree on permanent repairs with the adjuster.
Karol Rajkowski
Vice President · OYH Roofing
Karol Rajkowski is Vice President of OYH Roofing, an Oakville-based ICI flat-roofing contractor whose projects include the City of Mississauga building at 3185 Mavis Rd and the Marriott Hotel in Vaughan. Learn more about the OYH team.
Sources
- Water Damage and Flood Protection, Insurance Bureau of Canada.
- Types of business coverage, Insurance Bureau of Canada.
- Severe Weather Insurance Help, Insurance Bureau of Canada.
- Does my insurance cover damage caused by extreme cold?, Insurance Bureau of Canada, January 2025.
- Insurance glossary, Insurance Bureau of Canada: actual cash value and depreciation.
- Insurance Act, R.S.O. 1990, c. I.8, section 148, statutory conditions 6, 9 and 10, Government of Ontario.
- General Insurance OmbudService (GIO).
- Maintaining compliance, Professional Roofing (NRCA), February 2024.
- Tech Today, Professional Roofing (NRCA), October 2013: warranties and maintenance.
- Still water runs deep, Professional Roofing (NRCA), July 2012: the 48-hour ponding test.
OYH Roofing, 2120 Speers Rd, Oakville, ON L6L 2X8 · 1-833-775-7663 · info@oyhroofing.ca