How to Seal a Driveway
Sealing is maintenance, not repair. Sealer is a thin coating that protects a sound surface from water, UV, and oil. It will not fix a crack, level a low spot, or hold a crumbling edge together, and pretending otherwise wastes a weekend.
Fill every crack first. Sealer poured over an open crack sinks straight into it, leaves a shallow depression that looks sealed for about a month, and the crack reappears in full by the following spring. Fill, cure, clean, then coat.
Need your square footage before you buy? Run the numbers with our free square footage calculator, because sealer is sold by coverage rate and guessing costs you either a wasted bucket or a second trip halfway through.
Updated August 2026
A note on numbers. This page gives you dimensions, quantities and scope, not dollar figures. Material and contractor pricing varies by region, by season and by the specifics of your job, and we do not set any of it. Work out what you need here, then get quotes that can be compared to each other.
How to seal a driveway: the job in six steps
- Identify your surface. Asphalt and concrete take completely different products.
- Check the age and the weather window. New asphalt needs to cure first.
- Clean it thoroughly, including degreasing every oil spot.
- Fill cracks by width with the right filler, and let it cure.
- Apply the sealer by squeegee or sprayer at the labeled coverage rate.
- Keep off it for the full cure time before parking on it.
Plan on a full weekend: one day for prep and crack filling, one for sealing, and 24 to 48 hours after that before vehicles return.
Asphalt and concrete are not interchangeable
This is the single most expensive mistake in driveway sealing, and it happens constantly because both products sit on the same shelf in five gallon pails.
Asphalt sealers are coal tar or asphalt emulsion coatings. They're black, they're designed to bond to a bituminous surface, and they work by replacing the oils that UV light cooks out of asphalt over time.
Concrete sealers are acrylics, silanes, siloxanes, or epoxies. They either form a clear film on the surface or penetrate into the pores and repel water from inside.
Asphalt sealer on a concrete driveway is a common and expensive mistake. It does not chemically bond to portland cement. It sits on top as a black film, and within a season or two it peels, flakes, and lifts in sheets. Removing it means pressure washing, chemical stripping, or grinding, and full removal from a broom-finished concrete surface is close to impossible. You've turned an afternoon of maintenance into a removal job that costs many times more, or into a permanently blotchy driveway.
Concrete sealer on asphalt is a smaller disaster but still a waste. Most concrete sealers won't bond to a bituminous surface and either bead off or flake away, and you've spent the money for nothing.
Not sure which you have? Asphalt is black to gray-black, flexible, warm and slightly soft on a hot day, laid in one continuous mass with no control joints. Concrete is light gray to tan, hard in any weather, and cut or tooled into panels with control joints every 8 to 12 feet. If you're comparing a full replacement instead of maintenance, paver driveway cost has the numbers on the third option, and the concrete calculator tells you the yardage if you're pouring a new slab.
Timing: when to seal, and when not to
New asphalt has to cure first
Fresh asphalt is full of volatile oils that need to escape. Sealing it too soon traps them, leaves the surface soft, and gives you a driveway that scuffs under a turning tire and holds the imprint of a kickstand.
Wait 6 to 12 months after a new asphalt driveway is installed before its first seal coat. Most contractors say 6 months minimum, and in cooler climates a full year is safer. The surface tells you when it's ready: new asphalt is jet black and slightly oily, and it's ready to seal when it has faded to a dull charcoal gray.
New concrete is the opposite
Concrete wants to be sealed early, once it has cured. Most penetrating sealers go on 28 days after the pour, once the slab has reached design strength and surface moisture has come down. Some cure-and-seal products go on within hours of finishing. Follow the specific product's instructions, because this one varies by chemistry.
The weather window
| Condition | Requirement | Why |
|---|---|---|
| Air temperature | 50 F and rising, 55 F for most coal tar products | Below this the sealer won't coalesce into a film |
| Surface temperature | 50 F minimum, under 90 F ideally | Hot pavement flashes the water off before the sealer levels |
| Overnight low | Above 50 F for the following 8 to 12 hours | A cold night mid-cure ruins the film |
| Rain forecast | Dry for 24 hours before and 24 to 48 hours after | Rain on uncured sealer washes it into the storm drain |
| Sun | Overcast or early morning is better than midday sun | Fast flash-off causes lap marks and poor penetration |
| Season | Late spring through early fall in most of the country | Reliable temperatures both day and night |
Check the forecast twice: once for the day you apply and once for the following night. A 48 F overnight low after a 72 F afternoon will leave you with a streaked, powdery finish that has to be redone.
Step 1: clean it, and mean it
Sealer bonds to a clean surface and to nothing else. This step is the majority of the labor.
- Clear the surface. Sweep or blow off every leaf, pebble, and clump of dirt. A leaf blower is faster than a broom by a wide margin.
- Pull vegetation from cracks. Weeds growing through a crack have roots under the pavement. Cut them, then treat with a vegetation killer, and give it a few days.
- Scrub the edges. The turf line accumulates soil that has to come off, or the sealer stops an inch short of the edge and water gets in there.
- Pressure wash or hose and scrub. A pressure washer at 2,500 to 3,000 psi with a 25 degree tip works well on both surfaces. Keep the tip moving and don't sit in one spot on asphalt, which will erode the binder.
- Let it dry completely. 24 hours of dry weather minimum after washing, longer in humid conditions. Asphalt looks dry on the surface long before the cracks and edges are.
Oil spots have to be treated separately
Sealer will not bond over oil, period. Petroleum residue softens asphalt sealer and repels concrete sealer. If you skip this, you get a driveway with a set of permanent bare patches exactly where the car parks, which is the most visible part of the whole surface.
For oil and transmission fluid stains:
- Scrub with a degreaser made for driveways, or a strong detergent, using a stiff bristle brush. Rinse thoroughly.
- For soaked-in stains, use an oil spot primer. This is a specific product, sold in quarts and gallons next to the sealer, that seals the contaminated area so the topcoat can bond. It is inexpensive and it's not optional on a stain you can still see after degreasing.
- On concrete, a poultice of an absorbent powder mixed with a solvent pulls oil back out of the pores. It takes 24 hours and sometimes two rounds.
- Deep, old stains may never fully disappear. The goal is a bondable surface, not a cosmetic match.
Step 2: fill the cracks, sized by width
Crack filler and sealer are different products with different jobs. Match the filler to the crack width.
| Crack width | Product | Notes |
|---|---|---|
| Hairline, under 1/8 inch | Nothing, or the sealer itself | Sealer bridges these fine |
| 1/8 to 1/2 inch | Pourable or squeeze-bottle crack filler | Cold-pour asphalt emulsion filler, sold by the quart |
| 1/2 inch to 1 inch | Filler over backer rod, or hot-pour rubberized filler | Backer rod keeps you from pouring filler into a void |
| Over 1 inch, or crumbling edges | Cold patch asphalt or concrete patching compound | This is repair, not filling |
| Alligator cracking, a web of interconnected cracks | Do not seal over it | The base has failed; it needs cutting out and patching or repaving |
| Concrete control joints | Flexible self-leveling joint sealant | These are meant to move, use a joint product not a crack filler |
Order matters: clean the crack out first with a screwdriver, wire brush, or a blast of compressed air, then fill. Filler poured over loose debris fails at the bottom and drops out.
Let the filler cure before you seal. Most cold-pour fillers want 24 hours; some hot-pour products are ready in an hour. Read the tube. Filling and sealing on the same afternoon is a very common shortcut and it leaves soft, uncured filler under a hard topcoat, which cracks along every filled line.
Expect a shadow. A filled crack will always be visible through the sealer as a slightly different sheen. That's normal and it's not a defect.
Step 3: pick the right sealer
| Sealer type | Surface | Lifespan | Relative cost per pail | Notes |
|---|---|---|---|---|
| Coal tar emulsion | Asphalt only | 3 to 5 years | The cheapest of the six | Best fuel and oil resistance, deepest black, strongest odor, restricted or banned in a growing list of states and municipalities |
| Asphalt emulsion | Asphalt only | 2 to 4 years | Essentially the same as coal tar | Lower VOC, legal everywhere, more UV protection than fuel resistance, the common alternative where coal tar is banned |
| Fast-dry or acrylic-modified asphalt | Asphalt only | 3 to 5 years | Roughly double the plain emulsions | Dries in 1 to 2 hours, better color retention, costs more |
| Acrylic film-forming sealer | Concrete | 1 to 3 years | Higher again, and the shortest lived | Adds sheen and darkens the surface, can turn slick when wet unless you add grit, reapply often |
| Penetrating silane or siloxane | Concrete | 5 to 10 years | Pricier per pail than acrylic, far cheaper per year | Soaks in, invisible finish, no sheen, best freeze-thaw and de-icing salt protection, the right pick for most concrete driveways |
| Epoxy or polyurethane | Concrete, usually garage floors | 5 to 10 years | The most expensive here | Very durable, unforgiving prep requirements, slick unless broadcast with grit, generally overkill outdoors |
For a typical concrete driveway that sees winter and de-icing salt, a penetrating silane or siloxane is the right call. It doesn't change the look, it doesn't peel because there's no film to peel, and it lasts three to five times as long as an acrylic. For a typical asphalt driveway, asphalt emulsion or a fast-dry acrylic-modified product covers most people, and coal tar only if it's legal where you live and you want the maximum fuel resistance.
Check local rules on coal tar before you buy. Several states, plus many counties and cities, restrict or ban it over water quality concerns, and retailers in those areas simply won't stock it.
Step 4: how often, and why more often is worse
| Surface | Reseal interval | Signs it's time |
|---|---|---|
| Asphalt, established | Every 3 to 5 years | Faded to light gray, aggregate feels exposed and rough, water soaks in instead of beading |
| Asphalt, new | First seal at 6 to 12 months, then on the normal interval | Faded from jet black to charcoal |
| Concrete, penetrating sealer | Every 5 to 10 years | Water stops beading and soaks in dark |
| Concrete, acrylic film | Every 1 to 3 years | Sheen has dulled, film shows wear paths |
Over-sealing asphalt causes cracking and peeling. This is real and it's the opposite of what people assume. Every coat adds thickness, and sealer is much more brittle than the asphalt underneath. Build up four or five coats and you have a rigid crust bonded to a flexible base, and when the base expands and contracts with the seasons, the crust can't follow. It crazes into a network of fine cracks, then flakes and peels off in plates, taking the appearance of the driveway with it. Stripping over-applied sealer is expensive.
The rule: seal on a schedule the surface actually needs, not annually. An asphalt driveway sealed every year is being damaged, not protected. If your driveway still beads water and still looks dark, wait another year.
Same principle with coats. One properly applied coat at the labeled rate beats two heavy ones. A second thin coat is justified on a badly weathered, porous surface, and that's it.
Step 5: application
Squeegee versus spray
| Method | Best for | Pros | Cons |
|---|---|---|---|
| Squeegee and brush applicator | Most DIY asphalt jobs | Forces sealer into pores, thicker and more durable coat, no overspray | Slower, harder work, shows technique |
| Pump or backpack sprayer | Concrete penetrating sealers, thin coatings | Fast, even, no lap marks | Overspray risk, wrong for thick asphalt emulsions |
| Sprayer plus squeegee back-drag | Larger asphalt jobs | Speed with the working-in benefit | Two people or a lot of walking |
| Roller | Small concrete areas, acrylics | Cheap, controllable | Slow, can leave stipple texture |
Thick asphalt emulsions generally cannot be sprayed with a homeowner pump sprayer. They'll clog it. Use the squeegee applicator, which every store that sells sealer stocks cheaply.
Coverage rates and the worked example
Coverage varies by product and surface porosity, so the pail is the authority. Typical figures:
- Asphalt sealer: 250 to 400 sq ft per gallon, so a 5 gallon pail covers roughly 1,250 to 2,000 sq ft per coat. A rough, porous, never-sealed driveway lands at the low end.
- Penetrating concrete sealer: 150 to 250 sq ft per gallon on a broom finish, more on smooth troweled concrete.
- Acrylic concrete sealer: 200 to 300 sq ft per gallon.
Worked example. A two-car asphalt driveway, 20 feet wide by 40 feet long, is 800 sq ft. At 300 sq ft per gallon that's 2.7 gallons, so one 5 gallon pail covers it with margin, and a second pail is needed only if you're doing two coats or the surface is unusually porous. Your shopping list is that pail, a quart or two of crack filler, a squeegee, and a bottle of oil spot primer. Hiring the same driveway out costs more than that shopping list, but not by the margin most people assume, because the material is the same and a one-driveway job barely clears a contractor's minimum.
For a 24 by 24 concrete driveway, 576 sq ft, with a penetrating siloxane at 200 sq ft per gallon: 2.9 gallons, so buy a single 5 gallon pail. It is the most expensive pail on the shelf and it won't need doing again for the better part of a decade, which makes it the cheapest concrete sealer per year of protection.
Applying it
- Stir the pail thoroughly. Asphalt sealer settles hard. Use a drill with a mixing paddle for 3 to 5 minutes until there's nothing solid at the bottom.
- Cut the edges first with a brush, along the garage apron, the sidewalk, and the turf line. Tape or lay cardboard against anything you don't want black.
- Pour a ribbon across the driveway and pull it with the squeegee, working in strips 3 to 4 feet wide.
- Overlap each pass into the wet edge. Working into a partially dried edge causes lap marks that never go away.
- Work from the garage toward the street so you're never standing on fresh sealer.
- Don't chase a thin spot. Going back over sealer that has started to set drags it and leaves streaks. Fix it on the second coat if there is one.
Cure time before parking
| Stage | Asphalt sealer | Fast-dry asphalt sealer | Penetrating concrete sealer |
|---|---|---|---|
| Dry to touch | 4 to 8 hours | 1 to 2 hours | 1 to 4 hours |
| Foot traffic | 12 to 24 hours | 4 to 6 hours | 4 to 6 hours |
| Vehicle traffic | 24 to 48 hours | 12 to 24 hours | 12 to 24 hours |
| Turning wheels without scuffing | 48 to 72 hours | 24 to 48 hours | Not usually an issue |
That last row is the one people miss. A car can drive on at 24 hours and still scuff the surface if the wheels are turned while the vehicle is stopped. Drive straight in and out for the first few days, and don't crank the wheel on a parked car.
Barricade the driveway with caution tape and a couple of sawhorses. Delivery drivers and neighbors don't know it's fresh.
What actually drives the cost of sealing a driveway
Sealing is quoted per square foot, and then the square foot rate is bent by a handful of things. Here is what to look at, on your own shopping list or on a contractor's bid:
| Line item | What moves it | DIY versus contractor |
|---|---|---|
| Sealer itself | Sealer type is the biggest single swing. Concrete penetrating sealers cost several times what asphalt emulsion does per gallon | You buy pails; a contractor folds it into the per square foot rate |
| Coverage rate | Gallons needed is area divided by the coverage on the label, and a porous or never-sealed surface drinks noticeably more | Same math either way. This is why a first seal costs more than a resealing |
| Crack filler | Linear feet of cracks, and how wide they are. Anything over an inch stops being filling and becomes patching | Often a separate line on a bid. Ask before you compare quotes |
| Oil spot primer | How many stains survived the degreasing | Usually included in a bid, easy to forget on your own list |
| Tools | Squeegee, brush, mixing paddle. A one time purchase you keep | A contractor already owns them |
| Number of coats | Two coats roughly doubles material and time | Confirm which the bid assumes. This is the most common difference between two bids |
| Surface prep | Power washing, weed removal in cracks, and edging all take time before anything gets sealed | The bulk of the labor hours on any bid |
| Contractor minimum | Small driveways rarely beat the minimum charge, so a tiny job and a modest one often cost the same to hire | The reason DIY wins most clearly on small driveways |
| Coal tar restrictions | Where coal tar is banned the alternatives cost more per pail | Affects both equally |
Materials pricing moves with oil, labor swings hard between rural and metro markets, and coal tar restrictions change what's even available locally. Get two written quotes from local contractors on the same scope, and ask each of them the same three questions: how many coats, is crack filling included, and is oil spot priming included. That is where bids differ most, and a bid that looks low almost always answers one of those three differently.
When sealing is the wrong answer
Sealer is cosmetic and protective. It cannot save a failing driveway. Call a paving contractor instead if you see:
- Alligator cracking, a web of interconnected cracks over an area. The base under the pavement has failed. Sealing it hides it for one season and wastes the money.
- Potholes or spots that flex under a car. That's a base failure too.
- Crumbling, ravelled edges where the aggregate is coming loose in handfuls.
- Standing water that doesn't drain within an hour of rain. Sealing a birdbath just makes a shinier birdbath.
- Heaved or offset concrete panels. That's a slabjacking or replacement conversation.
- Widespread concrete spalling, where the surface is flaking off in sheets. Usually freeze-thaw damage or a bad original finish, and a sealer applied over it just peels with the flakes.
Permits are not normally required for sealing, which is maintenance. Replacing a driveway, changing its width, or altering the curb cut usually does require a permit, and in many towns anything that changes drainage or impervious surface area triggers a review. Check with your local building department before a replacement.
Old-house note: if you're working around a home built before 1978 and any painted surface, such as a garage apron edge or painted curb, needs prep, assume the paint contains lead until tested and do not sand or scrape it. Pressure washing painted surfaces on a pre-1978 home can also spread lead-contaminated debris, so keep the wand off the paint.
Frequently asked questions
How often should I seal my driveway?
Asphalt every 3 to 5 years, concrete with a penetrating sealer every 5 to 10 years, concrete with an acrylic film every 1 to 3 years. Judge by the surface, not the calendar: if water still beads and the color still looks good, wait. Sealing asphalt annually builds up a brittle crust that cracks and peels.
Can I use asphalt sealer on a concrete driveway?
No. Asphalt sealer doesn't chemically bond to concrete. It sits on the surface as a black film that peels and flakes within a season or two, and removing it takes pressure washing, chemical stripping, or grinding. Concrete needs an acrylic, silane, or siloxane product made for cement.
How long after new asphalt can I seal it?
Wait 6 to 12 months. Fresh asphalt needs time to release its volatile oils, and sealing too early traps them and leaves a soft surface that scuffs and holds tire marks. The visual cue is color: new asphalt is jet black, and it's ready to seal when it has faded to a dull charcoal gray.
Do I have to fill cracks before sealing?
Yes. Sealer is a thin coating that flows into an open crack and leaves a depression, so the crack reappears within a season. Clean the crack out, fill by width with the right product, and let the filler cure the full time on the label, usually 24 hours, before you apply sealer over it.
How long before I can drive on a sealed driveway?
24 to 48 hours for standard asphalt sealer, 12 to 24 hours for fast-dry formulas and most concrete sealers. Give it 48 to 72 hours before turning the wheels of a stopped car, because power steering against fresh sealer scuffs it even after it's hard enough to drive on.
Is coal tar or asphalt emulsion sealer better?
Coal tar resists gasoline and oil better and gives a deeper black, but it has a strong odor and is restricted or banned in a growing number of states and cities over water quality concerns. Asphalt emulsion is legal everywhere, lower odor, and fine for a residential driveway that isn't seeing fuel spills.
Can I seal a driveway myself or should I hire it out?
Sealing is genuinely DIY-friendly on a driveway under about 1,000 sq ft, and you'll save roughly 40 to 60 percent. Hire it out for large driveways, steep slopes, anything needing crack repair beyond simple filling, and any surface with alligator cracking or potholes, which need paving work rather than sealing.
What temperature do I need to seal a driveway?
At least 50 F and rising during application, with an overnight low staying above 50 F for the next 8 to 12 hours. Coal tar products often want 55 F. You also need 24 hours dry before and 24 to 48 hours dry after, and an overcast day beats direct midday sun.
Related: Measure before you buy with the square footage calculator, which turns your driveway dimensions into the coverage math in one step. If the surface is past sealing, compare replacement options with paver driveway cost and price a new slab with the concrete calculator.
