Hail and Asphalt Driveways in Denver
The storm itself is rarely the whole story; the calendar, the fresh coat and the cleanup crews matter just as much.
Hail season sits on top of sealing season
The Front Range is often described as the heart of Hail Alley. The Colorado Climate Center notes that some eastern Colorado counties average six or more hail days a year, among the most hail-prone ground in the country, and Denver7 reported that the Front Range sees three or four catastrophic hailstorms between mid-April and mid-August in a typical season. AccuWeather puts June as the most common month for hail in the state. Between 2013 and 2015, Colorado ranked second in the nation for hail claims, with 182,591 of them, behind only Texas.
That calendar lines up almost exactly with the window for sealing a driveway here. Sealer makers want 50 degrees and rising, with no drop below 50 for the next 24 hours, and NOAA's normals for Denver International Airport show that nights stay above that line reliably only in summer. The practical result is that the weeks a crew can seal a driveway are the same weeks the sky is most likely to throw ice at it, usually in the afternoon.
What the May 2017 storm showed
The costliest storm in Colorado records formed around noon on May 8, 2017, and did most of its damage between about 2:30 and 4 p.m. Golf-ball- and egg-sized hail fell on Lakewood and Wheat Ridge, a 2.75-inch stone was measured in Wheat Ridge at 3:05 p.m., and quarter- to golf-ball-sized hail fell downtown. Northwest and southwest Denver, Golden and Commerce City were also hit. The Rocky Mountain Insurance Information Association counted more than 100,000 homeowner claims and 167,000 auto claims.
For pavement, the lesson of that afternoon is about timing and aftermath. The storm arrived in the middle of a Monday afternoon in May, before the reliable sealing season had even started, and more than 100,000 homeowner claims meant a long run of roofing work afterward. For a driveway, that follow-up work deserves as much attention as the hail itself.
Fresh sealer and a storm forecast
A new coat of sealer needs about a day before it can take traffic, and manufacturers say not to apply it if rain is expected within 24 hours. Hail is precipitation with extra force, and a coat that has only skinned over on top is the most vulnerable surface on the property. Summer is also the wettest season at the airport, with 5.83 of the year's 14.30 inches falling from June through August, and the Colorado Climate Center describes hot afternoons on the plains that often end in thundershowers.
The defense is scheduling. A crew that starts early in the morning gives the coat its warmest, driest hours before storms usually build. If the forecast for the following 24 hours carries a real chance of thunderstorms, rebooking is cheaper than recoating. When a storm does hit a fresh coat, the sensible response is to let it cure fully, rinse off debris and have the crew inspect the surface; pitted or washed areas can be touched up with another thin coat once the weather settles.
Owners arranging Denver sealcoating in June should ask how the crew handles a storm day, whether rescheduling is free, and whether the quote includes a return visit to touch up a coat damaged before it cured.
After the storm: dumpsters, trucks and warm asphalt
A roof replacement puts a roll-off dumpster, a shingle delivery and several crew trucks on or near the driveway for days. Asphalt is a flexible material that softens in summer heat, and hauling companies warn that narrow metal rails and small wheels concentrate a loaded container's weight enough to leave dents and scrape marks on asphalt, especially in warm weather. Many ask customers to lay plywood under the rails first, and it is a reasonable request to make of any roofer.
In Denver the placement choice also has a permit side. A dumpster that stays on a private driveway needs no city permit, while one placed on a street, sidewalk or alley requires a right-of-way permit through the Department of Transportation and Infrastructure. Owners of older homes that load from the alley should know that the alley counts as public right-of-way for this purpose, even though it feels like part of the property.
Keeping the dumpster on the driveway avoids the permit, so the protection matters. Boards under the rails, a spot on firm pavement away from edges and fresh patches, and prompt removal once the roof is finished all reduce the chance of lasting marks.
A post-storm driveway check
Once the roof crew leaves, walk the driveway in daylight after the surface has dried. Most of what matters is visible, and the season timing works in an owner's favor: a check in July or August still leaves time for repairs and sealing before nights cool in September.
- Dents or rail marks where the dumpster sat, especially near edges
- Fresh cracks at the street edge or along the lawn from heavy trucks
- Oil or hydraulic drips from equipment that sat for days
- Scuffs where tires turned in place on a recently sealed coat
- Debris packed into existing cracks, which holds water through winter
- Nails, screws and shingle scraps in the joints and along the gutter
When to fix what the storm exposed
Oil drips need cleaning and priming before any new coat, or sealer will not bond there. Open cracks, whether new or newly noticed, should be filled before the median first freeze at the airport, October 6, so meltwater does not spend the winter working into the base. Shallow dents on otherwise sound asphalt are mostly cosmetic and can wait for the next resealing; a crushed edge or a broken section needs patching. The crack filling page explains the method and the typical pricing basis.
A hail year is also a reasonable moment to look at the whole schedule. If the driveway was last sealed three or more summers ago, pairing crack filling with a new coat in August closes the surface before the freeze-thaw season, which at the airport brings about 137 days a year when water in a crack freezes and thaws within the same day.
After the roof is fixed, request a driveway check and quote.
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Quick Answers
Should a Denver driveway be resealed right after a big hailstorm?
Only if it was already due. Hail on cured sealer usually does not justify a new coat by itself. The better sequence is to wait until roof work is finished, fix whatever the dumpsters and trucks did, fill open cracks, and then seal in the same summer if the last coat is three or more years old. Sealing before the roofers arrive just gives heavy equipment a fresh surface to mark.
Is a dumpster in the street better for the driveway than one on it?
For the driveway, yes, but it needs a right-of-way permit from the city's transportation department when it sits on a street, sidewalk or alley. On the driveway no permit is required, and plywood under the rails spreads the load. Asking the roofer where the dumpster will go, how long it will stay and whether boards are included takes a minute and prevents most of the damage.
What time of day do Denver hailstorms usually hit?
Summer storms on the plains tend to build in the afternoon, and the Colorado Climate Center describes hot days often relieved by afternoon thundershowers. The May 8, 2017 storm formed around noon and did its worst damage between about 2:30 and 4 p.m. That pattern is why crews start sealing early in the day and watch the afternoon outlook, since a coat needs about 24 dry hours.
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