# What damages a roof? The six enemies of every roof.

Mammoth Roofing & Exteriors · https://mammothroofs.com/blog/six-enemies-of-every-roof/ · (210) 934-9074

Hail, wind, sun and heat, water, trees and neglect. Every Texas roof faces all six, and each one leaves its own evidence. Here is how to spot each one, and what it costs to leave it.

_11 min read · Updated November 1, 2026_

**Key points**

- Hail does the most sudden damage in Texas. Stones about an inch across, the size of a quarter, can damage shingles, and NOAA counts that size as severe.
- Wind works from the edges in. The eaves, rakes, hips and ridge take more uplift than the middle of the roof, so that is where roofs fail first.
- Sun and attic heat age a shingle roof from both sides. An asphalt roof lasts 15 to 30 years in Texas, and the attic decides where it lands in that range.
- Most leaks start at a pipe boot, a flashing, a valley or a lifted shingle, and most begin as repairs that typically cost $500 or less.
- Neglect makes the other five expensive. A check once a year, and after any hail or high wind, catches small problems while they are cheap.

## What damages a roof, from fastest to slowest.

A roof rarely fails all at once. Six things wear on it, some in one afternoon and some over twenty summers, and most Texas roofs that leak have been worked on by more than one of them. Hail and wind do their damage in minutes and leave dated evidence. Sun, heat and water work slowly. Trees and neglect make every other one worse.

Each section below covers what the enemy does, how you spot it from the ground, and what it costs to leave it, with every number traced to its source. None of it needs a ladder. If you see the signs on your own roof, the next step is a free inspection, not a climb.

## 1. Hail.

Hail is the enemy Texas is known for. Our town pages count ten years of reports from trained spotters for the National Weather Service: 21 days with hail an inch or larger within 10 miles of San Antonio, and 38 and 14 days on the same measure for Fort Worth and Austin. The largest stone logged within 10 miles of San Antonio in the last three years was 2.5 inches, on March 21, 2024. NOAA calls a storm severe when its hail reaches an inch, about the size of a quarter, and the Weather Service now flags golf-ball hail (1.75 inches) as a considerable damage threat and baseball hail (2.75 inches) as destructive.

Hail does two things to an asphalt shingle. It knocks off the granules that shield the asphalt from the sun, and a big enough stone bruises or cracks the fiberglass mat underneath. A bruise is a soft spot an inspector can feel with a thumb, and it usually leaks a season or two later. Class 4 shingles, which pass the UL 2218 test of a 2-inch steel ball dropped from 20 feet without cracking, resist most of the hail that falls on San Antonio, and many Texas insurers discount them. No roof is hail-proof.

**How you spot it.** Granules collecting in the gutters and at the downspouts, dents in the gutters, vents and air-conditioner fins, and dark spots on the shingles where the granules are gone. On the roof, an inspector chalks a 10-by-10-foot test square on each slope and counts the hits inside it; most bruising cannot be seen from the ground.

**What it costs to ignore.** Most policies want storm damage reported promptly, and the longer you wait, the more of the damage an adjuster can put down to age. A bruised roof also keeps shedding granules until the leak arrives. Our [storm damage repair](https://mammothroofs.com/services/storm-damage-repair/) page covers the claim, and the guide to [what to do after a storm](https://mammothroofs.com/guides/what-to-do-after-a-storm/) covers the first 48 hours.

## 2. Wind.

Wind attacks a roof from the edges in. FEMA's guidance on sloped roofs notes that the roof border, the eaves and the rakes, is more at risk from wind uplift than the rest of the roof, and it recommends extra attachment for shingles along the eaves, rakes, hips and ridges. That is where wind damage usually shows: a course lifted at the eave, ridge caps gone, shingles folded back along a rake. Shingle makers know it too; CertainTeed's warranty, for one, ties its higher wind coverage to its own starter shingles along the eaves and rakes and its own caps along the hips and ridge.

Each asphalt shingle is held by its nails and by a seal strip, a line of adhesive that bonds it to the course below. Heat ages the strip, a gust gets under the edge, the bond breaks and the shingle folds back. Some reseal in the next warm spell. Some never do, and a shingle that has folded back has often cracked across the top. We nail six per shingle on every roof for this reason.

**How you spot it.** Shingles or ridge caps in the yard after a blow, shingles that sit slightly raised or show a straight crease across the tab, bare strips along the eaves or the ridge, and a new stain on a ceiling near an outside wall.

**What it costs to ignore.** A wind-damaged shingle repair typically costs $500 or less, the figure our [roof repair](https://mammothroofs.com/services/roof-repair/) page publishes. Left alone, the open edge lets wind-driven rain under the course, and the next storm lifts its neighbors until the repair is a whole slope.

## 3. Sun and heat.

Texas sun works on a roof every day, from both sides. From above, ultraviolet light dries the asphalt in a shingle until it turns brittle, and the granules loosen and wash into the gutters. From below, a poorly ventilated attic bakes the deck: our [ventilation guide](https://mammothroofs.com/guides/roof-ventilation/) puts a Texas attic at 140°F on a July afternoon, and over an attic like that a shingle rated for 30 years can curl in twelve.

That is why the same shingle lasts so differently here. An asphalt roof in Texas lasts 15 to 30 years, and where it lands in that range depends less on the shingle than on the attic under it. Intake vents at the soffits and exhaust at the ridge, sized to the attic, keep it nearer the outdoor temperature; the [ventilation calculator](https://mammothroofs.com/blog/roof-ventilation-calculator/) gives a starting point for yours. It matters to the warranty as well: CertainTeed's shingle warranty cuts any shingle on an inadequately ventilated deck to a reduced 10-year limited warranty.

**How you spot it.** Granules in the gutters after an ordinary rain, bare or shiny patches, shingles curling at the corners or cupping in the middle, and an upstairs that stays hot into the night. In the attic: dark stains on the underside of the deck and rusty nail tips.

**What it costs to ignore.** A roof that loses a decade to heat is a replacement bought ten years early, and our [cost guide](https://mammothroofs.com/guides/what-does-a-new-roof-cost/) puts a typical San Antonio replacement at $5,000 to $15,000. Balanced ventilation, fixed when the roof is replaced, is the cheapest year you can add to a roof.

## 4. Water.

Every other enemy ends in water. A roof is a set of overlaps that sheds rain downhill, and it leaks wherever an overlap is broken, at a crack, a seam or a place where the roof meets something that is not roof. The five leaks we find on almost every Roof Grade are the same five our [roof repair](https://mammothroofs.com/services/roof-repair/) page lists:

- **Cracked pipe boots.** The rubber collar around a plumbing vent is an $8 part, and the Texas sun kills cheap rubber in about five years.
- **Wind-lifted shingles**, with seal strips broken by a north wind.
- **Chimney and wall flashing.** Where the roof meets brick or siding, metal flashing should step up the wall under a counter flashing. Caulk was never a flashing.
- **Valleys**, where two slopes meet and water runs fastest.
- **Leaks that only happen in heavy rain**, usually a pipe boot, a nail pop or a flashing, found from the attic rather than the street.

**How you spot it.** A stain on a ceiling or at the top of a wall, a drip in the attic after rain, damp or flattened insulation, a musty smell. Water runs along the framing before it drips, so the stain is often several feet from the hole.

**What it costs to ignore.** Most of these start as small repairs: our roof repair page puts a pipe boot replacement at typically $500 or less and chimney or wall flashing at about $500 to $1,500. Left for a few seasons, the same leak rots the decking and soaks the insulation, and a major repair across several areas runs $1,500 to $5,000.

## 5. Trees and debris.

Shade is welcome in a Texas summer, but trees do a roof more harm than most people expect. A branch resting on the roof scrubs the granules off as it moves, and in a storm it can crack shingles or come through the deck. Leaves pile up in the valleys and gutters, where they hold water against the roof and push it back under the edge. Damp, shaded slopes grow moss and algae that keep the shingles wet, and branches over the roof give squirrels and raccoons a way up to the vents and soffits.

**How you spot it.** Branches touching or hanging over the roof, worn patches under them, debris lying in the valleys, gutters that overflow in a normal rain, dark streaks on shaded slopes, and chewed vents or soffit edges.

**What it costs to ignore.** The fixes are cheap. Trim the limbs back, and keep the gutters clear at least twice a year and again once the leaves come down in the fall, as our [roof maintenance](https://mammothroofs.com/services/roof-maintenance/) page advises. What they prevent is not: a limb through the roof in a storm becomes an insurance claim, and our [deductible guide](https://mammothroofs.com/guides/roof-insurance-deductibles/) shows how a percentage deductible can leave thousands of dollars of it with you.

## 6. Neglect.

The last enemy is the one that makes the other five expensive. A roof nobody looks at collects small problems: a cracked boot, a nail backing out, dried sealant at a vent, a torn screen, a blocked soffit. None of it leaks this year; all of it leaks in three, usually in the storm that also brings the hail.

The cure is dull and cheap. Have the roof looked at once a year and again after any hail or high-wind event, and twice a year for older roofs and heavily treed lots. That is the schedule on our roof maintenance page, and a dated photo record from each visit earns its keep when a storm does come, because it shows the roof the day before.

**How you spot it.** Usually you cannot, which is the point. Most of these problems are invisible from the ground, and some only show from the attic.

**What it costs to ignore.** Our [repair or replace guide](https://mammothroofs.com/guides/repair-or-replace/) puts minor repairs at $300 to $1,500, buying 5 to 10 more years on a roof with life left, and a full replacement at $5,000 to $18,000 and up. Neglect is how a roof skips from the first number to the second.

## A worked example: one pipe boot, two outcomes.

Two neighbors have shingle roofs of the same age, and on both the rubber boot around the bathroom vent pipe has cracked in the sun.

- **The first neighbor** has a yearly check. The inspector finds the crack before it leaks and replaces the boot on the visit. On our roof repair page, a pipe boot replacement typically costs $500 or less.
- **The second neighbor** notices nothing until a stain spreads across the bathroom ceiling after a spring storm. Water has been running down the pipe for months: the deck around it is soft, the insulation is wet and the drywall has to come out. That is a major repair, which our repair guide puts at $1,500 to $5,000, before anyone paints the ceiling.

The difference between them was one visit a year.

## What to do about the six.

- After any storm with hail near an inch or a strong wind, walk around the house and look for granules, dents, lifted shingles and debris on the roof.
- Photograph what you find from the ground, with the date showing.
- Check the attic after heavy rain for drips, stains and damp insulation.
- Keep the gutters and valleys clear and the branches trimmed back.
- Have the roof inspected once a year, and again after any hail or high wind.
- Stay off the roof. Wet shingles and loose granules are how homeowners get hurt.

## Frequently asked

How long does a roof last in Texas?An asphalt shingle roof lasts 15 to 30 years here, and the attic under it decides where in that range it lands. Standing seam metal runs 40 to 70 years. Hail, wind and neglect shorten either; a ventilated attic and a yearly check lengthen them.

What does hail damage look like on a roof?On asphalt shingles: dark spots where the granules have been knocked off, soft bruises an inspector can feel, and cracks after a big stone. Around them you usually see dents in the gutters, vents and other soft metal. A trained inspector counts the hits in a 10-by-10-foot test square on each slope.

Can small hail damage a roof?It can. Hail about an inch across, the size of a quarter, can damage shingles, and even smaller hail wears away the granules that protect them. Older shingles that have already lost granules are the most exposed, so if the stones on your lawn were near an inch, have the roof checked.

What damages a roof the most in Texas?Suddenly, hail and wind. Slowly, sun and attic heat, which take years off a shingle roof every summer. Water is how all of them end up costing money, and neglect is what lets small problems grow.

Can a roof be damaged without leaking?Yes, and most damage starts that way. A hail bruise, a broken seal strip or a cracked pipe boot can sit for months before water gets through, which is why an inspection checks the shingles, the flashings and the attic, not only the ceilings.

Does homeowners insurance cover this kind of damage?Sudden damage from a dated storm, such as hail or wind, is often a claim, minus your deductible; wear from sun, heat, age and neglect never is. Policies differ, so read yours, and see our [insurance claims](https://mammothroofs.com/services/insurance-claims/) page for how a claim runs.

#### Sources and notes

- NOAA, "Severe storms" (a storm is severe with hail of one inch, about a quarter, or wind gusts of 58 mph): [noaa.gov](https://www.noaa.gov/explainers/severe-storms)
- National Weather Service, "New damage threat categories for severe thunderstorm warnings" (1.75-inch hail considerable, 2.75-inch destructive): [weather.gov](https://www.weather.gov/lot/SevereThunderstormWarningsUpdate)
- National Weather Service Local Storm Reports via the Iowa Environmental Mesonet ([mesonet.agron.iastate.edu](https://mesonet.agron.iastate.edu/lsr/)), counted for ten years on our town pages for [San Antonio](https://mammothroofs.com/locations/san-antonio/), [Fort Worth](https://mammothroofs.com/locations/fort-worth/) and [Austin](https://mammothroofs.com/locations/austin/)
- FEMA P-2181, Fact Sheet 3.3.1, "Roof systems: sloped roofs" (the roof border at greater risk from uplift; extra attachment along eaves, rakes, hips and ridges): [fema.gov](https://www.fema.gov/sites/default/files/documents/fema_p-2181-fact-sheet-3-3-1-roof-systems-sloped-roofs.pdf)
- CertainTeed, asphalt shingle limited warranty (the wind warranty upgrade's starter and cap conditions; the reduced 10-year limited warranty on inadequately ventilated decks), from CertainTeed's warranty documents: [certainteed.com](https://www.certainteed.com/products/documents-downloads?documentCategory=Warranty&documentRegion=US&documentLanguage=EN&productCategory=Residential+Roofing)
- UL 2218 Class 4 impact test, as described in our [metal vs asphalt guide](https://mammothroofs.com/guides/metal-vs-asphalt/)
- Mammoth Roofing & Exteriors: [roof repair](https://mammothroofs.com/services/roof-repair/) (the five leaks; repair prices), [repair or replace](https://mammothroofs.com/guides/repair-or-replace/) (roof life; repair and replacement bands), [ventilation](https://mammothroofs.com/guides/roof-ventilation/) (attic temperature), [roof maintenance](https://mammothroofs.com/services/roof-maintenance/) (the inspection schedule; gutters and trees), [the cost guide](https://mammothroofs.com/guides/what-does-a-new-roof-cost/) and [the deductible guide](https://mammothroofs.com/guides/roof-insurance-deductibles/)

## Know where your roof stands.

The Roof Grade is free: attic first, every slope photographed, and a written grade from A to F. If everything is fine, we tell you.