Hot rubberized crack filling for driveways, shared rear drives and parking lots in Philadelphia and the Pennsylvania suburbs. A crack is not damage yet. It is the opening that lets the damage in. Close it properly and the asphalt either side of it keeps doing its job for years. Leave it, and the ground underneath starts to take water it was never meant to hold.
Width decides almost everything about how a crack is treated, so it is the first thing to check. Push a coin into it, or hold a tape measure across it at the widest point.
| What you see | What it gets |
|---|---|
| Hairline, thinner than about an eighth of an inch | Usually left for the sealer to close. Too thin for filler to get into. |
| About a quarter inch up to roughly an inch | The range hot rubberized filler is made for. Cleaned out and filled. |
| Wider than about an inch, or deep enough to see stone | Too wide for filler alone. It sinks and slumps. Built up in layers or patched. |
| Cracks joined into a web of small pieces | Not a crack filling job. See the next section. |
Two other places get filled whatever their width: the seam where the asphalt meets a concrete curb, garage slab or walk, and the ring around a drain inlet. Water collects at every one of those joins, and every one of them opens a little more each year.
When single cracks join up into a pattern of small many sided pieces, the way the skin on an alligator's back looks, the problem is no longer on the surface. The layers underneath have lost their support, usually because water has been getting into the base for a while, and the asphalt is flexing every time a car rolls over it.
Pouring filler into that web costs a lot of material and changes nothing. The pieces keep moving, the filler tears loose, and by the following spring the area is lower than before. The honest repair is to cut the whole section out down to firm ground and put new hot asphalt back, which is covered on the driveway and asphalt repair page. If a quote offers to crack fill an area like this, ask why.
Filler only works if it grips both walls of the crack. Most of the difference between a fill that lasts several winters and one that pulls away in the first is done before the kettle is even opened.
Hot pour. A rubberized asphalt compound melted in a heated kettle and applied hot. As it cools it sets into a flexible, sticky seal that stretches when the crack opens in the cold and squeezes back as it closes in summer. This is what a professional crack filling job means, and it is what goes into cracks on our sealing jobs.
Cold pour. A liquid filler sold in jugs, poured straight into the crack. It is better than nothing and easy to use. Most of it is water based, so it shrinks as it dries, often ends up below the surface, and tends to need a second application within a season or two.
The caulk tube. Squeezed in with a caulking gun. Fine for a hairline crack or a few feet around a step. On a driveway with any real amount of cracking it sits on top rather than inside, and it does not flex the way hot pour does. If you want to handle small cracks yourself between visits, this is the tool for it, and sealing your own driveway covers the rest of the do it yourself side.
Asphalt is a thin skin laid over a bed of compacted stone and soil. The skin is what you drive on, but the bed is what carries the weight. As long as that bed stays drained and firm, the surface above it can crack a little and still hold.
An open crack changes that. Rain and snowmelt run straight down it into the base. Philadelphia winters rarely freeze once and stay frozen. They cross the freezing point over and over, and each time the water in the base expands, lifts the surface a fraction, and settles back looser than it was. By late winter the ground under a cracked section is saturated and soft, and that is when the edges of the crack start to break off and a pothole appears in what was a single line in the autumn.
So the useful time to close cracks is before the cold, when the base is still dry and firm. A crack filled in September keeps the water out all winter. The same crack filled in April is sealing in whatever damage the winter already did.
Sealer is a thin coat. Spread over an open crack, it bridges the gap for a few weeks and then splits along the same line as soon as the crack moves, which leaves a neat black crack in a new black surface. That is why crack filling happens first on every sealing job, as part of the same visit, and why it is inside the sealing price rather than an extra.
Hot filler has to cool and firm up before the sealer goes over it. The filled lines stay slightly visible under the new coat, a little glossier than the surface around them. That is normal, and on a driveway that has been sealed a couple of times they fade into the rest of the surface.
Cracks are at their widest in cold weather and narrowest in the heat. Filling in the cooler shoulders of the season, spring or early autumn, catches them near the middle of their range, so the filler is neither stretched thin all winter nor squeezed up out of the crack in July. On a sealing job the filling follows the sealing schedule, late April through mid-October. Filling on its own needs dry cracks and ground that is not frozen rather than the warmth sealer needs, so it can run a little later into the autumn when the weather allows.
Plan on checking the cracks every year and refilling every two or three. Filler that has done its job for a few winters will have hardened, and new cracks will have opened near the old ones.
On a parking lot the cracks follow the traffic. Expect the most along the drive lane, at the turn in from the street, around catch basins, and along the long seam where the lot meets the curb or the building. Lots that were widened or patched in the past also crack along every old joint between the two pavements.
Every crack on a lot is walked and measured, because on older commercial asphalt the amount of cracking can be far more than it looks from a car, and it drives how much time the job takes. Filling runs a section at a time around your open hours, and a filled section can take traffic again once the filler has cooled. After that the lot is sealed and restriped, covered in more detail on the commercial sealcoating page.
When the cracks are filled as part of a sealcoating job, they are inside the one price per square foot, along with small patches and restriping where there are lines. No per foot surprise on the day. Crack filling ordered on its own is quoted per job after a look, because the time depends on how many cracks there are, how wide they run and whether they need routing. Either way you see one written number before work starts.
Can I have the cracks filled and skip the sealing? Yes. On a driveway that was sealed recently, or where the budget only stretches to one job this year, filling on its own is the part that protects the base.
How soon can I drive on it? Once hot filler has cooled, usually well inside an hour. If the driveway is also being sealed, the sealer's drying time is what decides when the car goes back on.
Will the cracks come back? Some will open again at the edges, and new ones form over time. Filler is maintenance, not a cure, which is why it is redone every few years.
Is a crack along the garage slab worth filling? Yes. It is one of the most important ones, because the water that gets in there runs under the driveway and toward the house.
Send the address through the form and mention cracks. A photo of the worst area with a coin next to it helps. You will be told which cracks need filling, whether any area is past that and needs a patch, and one price. The work is carried out by local independent contractors.
