A summer hailstorm can strip years off a roof in about ninety seconds. If you have just watched marble-sized or golf-ball-sized ice pelt your shingles, you are probably wondering exactly what materials are recommended for roof hail damage repair and whether your existing roof can even be patched or needs a full section replaced. The honest answer depends on your roofing material, the severity of the impacts, and how the repair interacts with your insurance claim.

At Universal Roofs, we have been inspecting and repairing hail-damaged roofs across the GTA since 2005, and we see the same question every storm season: homeowners want to know which shingles, sealants, flashing, and underlayment products actually hold up the next time hail rolls through Toronto. This guide walks through the materials professionals use for hail damage repair, why some products outperform others, and how to make sure your repair is done right the first time.

Ontario summers bring convective storm systems that can drop hail with very little warning, and freeze-thaw cycles the rest of the year mean any damage left unrepaired tends to get worse, not better. Small cracks and bruised shingle mat let moisture in, and by winter that moisture has expanded and split the shingle further. Choosing the right repair materials now protects the rest of the roof structure later.

How Hail Actually Damages a Roof

Before choosing materials, it helps to understand what hail does to a roofing system. Hailstones bruise the shingle mat, knock granules loose, and in severe cases crack the fiberglass or organic base layer outright. On metal roofing, hail dents panels and can chip protective coatings. On flat and low-slope roofs, hail impacts can puncture membranes or accelerate UV breakdown at weak points. None of this damage is always visible from the ground, which is why a proper inspection always precedes material selection.

Granule loss is the most common and most underestimated form of hail damage. Those granules are not decorative — they shield the asphalt layer from UV radiation. Once a patch of shingle loses its granules, that spot ages faster, becomes brittle, and is far more likely to crack during the next freeze-thaw cycle. This is why even “cosmetic” hail damage should be assessed by someone who knows what to look for, ideally through a full roof repair inspection rather than a quick visual check from the driveway.

Impact severity generally falls into a few categories that determine which materials and repair method apply. The table below summarizes what we typically find during post-storm inspections.

Impact-Resistant Shingles: The Foundation of a Durable Repair

If your existing roof is asphalt shingle, the single most important material decision is whether to repair with standard shingles or upgrade to Class 4 impact-resistant shingles. Class 4 shingles are rated under UL 2218, the industry standard test that drops steel balls from height onto a shingle sample to simulate hailstone impact. A shingle earns a Class 4 rating when it resists cracking under the most severe test level.

These shingles use a modified asphalt formulation, often blended with polymer (SBS-modified asphalt), which gives the mat more flexibility and allows it to absorb impact energy rather than crack. For a homeowner repairing storm damage, using Class 4 shingles on the repaired section — or across the whole roof if enough of it was affected — is the clearest way to reduce the odds of repeat damage next season.

Many insurers in Ontario also offer a premium discount for roofs upgraded to impact-resistant shingles, which can offset some of the modest cost difference over a few years. If you are unsure whether your current shingle brand and colour are still available, our team can match it or recommend the closest equivalent during a repair estimate.

Underlayment and Sealants That Support the Repair

Shingles get most of the attention, but the materials underneath and around them matter just as much for a hail repair to actually last. A synthetic underlayment (rather than older felt paper) is now the standard choice because it resists moisture absorption and stays intact if water finds its way past a compromised shingle before the repair is complete. Self-adhering rubberized membrane is used at vulnerable points — eaves, valleys, and around any penetration — to create a secondary water barrier.

Sealants matter more than most homeowners realize. Roofing cement and butyl-based sealants are used to reseal shingle tabs, flashing edges, and nail heads exposed during the repair. Using a high-quality, UV-stable sealant rather than a generic caulk prevents the repair from failing prematurely when exposed to Toronto’s summer heat and winter freeze-thaw swings. Cheap sealants dry out and crack within a season or two, which is a common reason “repaired” hail damage reappears the following year.

Flashing is another area where material choice determines longevity. Dented aluminum or steel flashing around chimneys, skylights, and vent stacks should be replaced rather than bent back into shape, since bent flashing rarely seals properly again. If your skylight flashing was affected by the same storm, it is worth having it checked alongside the shingle repair — our skylights team frequently finds hail has also compromised the flashing kit around older skylight units, and in some cases a full skylight replacement ends up being more cost-effective than repeated flashing patches.

Materials for Flat and Low-Slope Roof Hail Repairs

Not every GTA home has a pitched shingle roof — many additions, garages, and commercial buildings have flat or low-slope sections that need a different repair approach entirely. Hail on a TPO or EPDM membrane roof usually causes punctures or accelerated wear at seams rather than the granule loss seen on shingles. Repairing these requires membrane-specific patch kits, seam primer, and heat-welding or adhesive bonding depending on the membrane type.

Using a patch material that is not chemically compatible with the existing membrane is one of the most common mistakes we see from smaller repair crews. TPO patches will not properly bond to an EPDM membrane and vice versa, so matching the patch material to the existing roof system is essential, not optional. For larger areas of hail damage on a flat roof, a full membrane section replacement is often more reliable than multiple patches, and our flat roofing specialists can advise on whether a patch or a section replacement makes more sense for your situation.

Attic ventilation is worth checking at the same time, since any leak from hail damage that reached the deck can introduce moisture into the attic space. If your attic insulation shows signs of dampness following a storm, that is a signal the roofing membrane or shingle underlayment was breached and needs more than a surface-level repair.

Matching Materials to Your Existing Roof

One challenge unique to repair work — as opposed to a full roof replacement — is matching new materials to an older roof that has weathered and faded over several years. Asphalt shingle colours shift subtly with UV exposure, so a repair patch using brand-new shingles can look noticeably different from the surrounding field for a season or two until it weathers in. A good contractor will source the closest available match, sometimes pulling shingles from a less visible slope (like a rear-facing section) to patch a highly visible front-facing area, then using the new shingles where they are less noticeable.

If your roof is more than twelve to fifteen years old and hail damage is widespread rather than isolated to one slope, a full reroof with upgraded impact-resistant materials is often more cost-effective than a series of patch repairs over the following years. We walk homeowners through this cost-benefit comparison honestly rather than defaulting to the larger job, because a well-matched repair is often the right call for a newer roof with isolated damage.

Insurance Considerations and Material Documentation

Most hail damage repairs in the GTA involve a homeowner’s insurance claim, and the materials you choose can affect both the claim outcome and your future premiums. Insurers typically require photo documentation of the damage before repairs begin, along with a written estimate specifying the exact materials and quantities used. Using recognized, code-compliant materials — CSA or ULC-listed shingles, flashing that meets Ontario Building Code requirements, and underlayment rated for the local climate — helps avoid disputes during the claims process.

Some insurance policies now explicitly reference impact-resistant shingle ratings, either requiring them for claim approval in high-hail-risk zones or offering a rebate if you choose to upgrade during the repair. It is worth asking your adjuster directly whether Class 4 shingles qualify for any premium reduction before finalizing your material choice, since this can meaningfully change the economics of upgrading versus a like-for-like replacement.

Keep every material invoice, product data sheet, and warranty card from your repair. If a manufacturer defect surfaces years later, or if another storm causes damage nearby, this documentation makes a second claim faster and more straightforward to process.

Material Costs and What Drives the Price

Homeowners often ask why one hail repair quote is significantly higher than another for what looks like the same job on paper. The answer almost always comes down to material grade. A repair using standard 3-tab shingles and generic sealant will cost less upfront than one using Class 4 shingles, synthetic underlayment throughout, and new metal flashing — but the cheaper repair is also more likely to need attention again within a few years, particularly given how much freeze-thaw stress GTA roofs experience each winter.

Labour is a smaller variable than most people expect; the material specification is usually what separates a budget quote from a premium one. When comparing estimates, ask specifically which shingle class, underlayment type, and flashing material each contractor is proposing, not just the total price.

When Repair Isn’t Enough: Recognizing the Need for Replacement

Materials can only do so much if the underlying roof structure has taken too much cumulative damage. If hail impacts are spread across most slopes rather than concentrated on one exposed side, or if the roof was already near the end of its expected lifespan before the storm, patch repairs using even the best materials may only delay a full reroof by a season or two. In these cases, a complete roof replacement using Class 4 shingles across the entire surface gives you uniform colour, a single consistent warranty, and the strongest defence against the next storm.

We always recommend getting an honest opinion in writing before committing to either path. A written scope that lists every material by name and grade — not just “shingles” or “flashing as needed” — protects you if a dispute arises later, whether with your insurer or the contractor.

Serving the Greater Toronto Area

Hailstorms do not respect municipal boundaries, and we field repair calls across the whole region every storm season. Our crews regularly work in Toronto, Peel Region, York Region, Halton Region, and Durham Region, and material sourcing is rarely an issue since most major shingle and membrane manufacturers keep distribution centres within the GTA. That means a hail-damaged roof repaired in July can be matched to the original shingle line without the multi-week delays some homeowners worry about.

You can read what other GTA homeowners have said about their hail repair experience with us on our reviews page, and our FAQ page covers additional questions about scheduling, insurance paperwork, and warranty terms. For background on our licencing and history in the region since 2005, visit our about page.

Need Help With What Materials Are Recommended?

Choosing the right shingles, underlayment, flashing, and sealants makes the difference between a hail repair that lasts and one that fails again next storm season. Universal Roofs has spent two decades matching the right materials to the right roof across the GTA, and we are happy to walk you through your options in plain language before any work begins.

Call us today at (416) 732-2421 or request a free inspection to get started.

Universal Roofs proudly serves Toronto, Mississauga, Brampton, Vaughan, Markham, Oakville and the GTA since 2005.