Asphalt Repair

Every defect is telling you something

Asphalt fails in a small number of recognizable patterns, and each one points at a different cause. Learning to tell them apart is what separates a repair that holds from a repair that is back on the schedule next year.

The single most useful distinction is direction of travel. Damage that begins in the wearing course and works downward can be addressed from above, and treatments applied there earn their keep. Damage that begins in the layers beneath and works upward cannot be reached from above at all, whatever is applied.

Owners lose a great deal of money to that distinction, usually in the form of sealing or overlaying a lot whose base is failing. The work is done properly, the lot looks better for a season, and it fails on exactly the schedule it was already on.

So the first question on any repair is never how to fix it. It is what caused it, and whether what caused it is still happening.

Alligator cracking

Interconnected cracking in a pattern like reptile skin, almost always in wheel paths, at entrances, or where heavy vehicles turn. This is the clearest base failure signal in the trade.

What it means is that the pavement is flexing under load because the material underneath has lost the ability to support it, and the asphalt is breaking up as a result. The cause is under the surface, not on it.

It cannot be sealed. It cannot be overlaid with any expectation that the pattern will not come back through. The area has to be removed, the base repaired or replaced, and new asphalt placed to the specification the loading actually requires.

That is why a relatively small alligatored area costs more to fix properly than a large area of surface work, and why a bid that proposes sealing it is either not reading it correctly or is selling something cheaper than what is needed.

Potholes

A pothole is usually alligator cracking that has progressed until pieces have come out, accelerated by water getting into the base and, in this climate, by that water freezing.

The useful question is never how to fill it. It is why it appeared where it did and not two feet to the left.

Potholes that recur in the same location after being filled are telling you that either the base has failed there or water is getting in and not getting out. Refilling them is a recurring charge rather than a repair.

There is a legitimate place for a temporary fill — a hazard in the middle of winter has to be dealt with when it appears, not in April. What matters is being honest that it is temporary, and scheduling the real repair for the season.

Longitudinal and transverse cracking

Single cracks running with or across the direction of travel are frequently surface-level in origin: thermal movement, oxidation of the binder, or joints from the original paving opening up.

These are genuinely worth sealing, and along the Front Range sealing them promptly is one of the highest-return things on a maintenance schedule. An open crack is a route for water into the base, and in a climate with this many freeze-thaw cycles that route gets wider every winter.

Where transverse cracks appear at regular intervals across a lot, they are frequently reflecting joints or cracks in an older pavement underneath an overlay, which is a different situation and one that sealing manages rather than solves.

Rutting, shoving and depressions

Depressions running along wheel paths, or material pushed up into ridges where vehicles brake and turn, indicate that the pavement is deforming rather than cracking.

Causes divide into two. Either the mix and thickness are not adequate for the loads being applied, which shows up where heavy vehicles maneuver, or the base and subgrade are consolidating under load, which shows up as broader depressions.

Ruts also collect water, which then works on the base and accelerates everything else. A rut is therefore both a symptom and a new cause, which is why they tend to get worse at an increasing rate.

Where this appears at a dumpster pad, a delivery entrance or a drive-through window, the loading is the story and the repair has to change the specification rather than replace like for like.

A pale, gritty surface shedding stone

Sunlight breaks down the binder that holds the aggregate in place, and the surface turns from black to gray as it goes. Past a point the stone itself starts working loose, the texture turns coarse underfoot, and sweeping the lot produces a pile of what used to be the lot.

At Front Range elevation this runs faster than most owners expect, and it is the one failure mode that surface treatment is genuinely designed to slow. A sound but oxidizing surface is the case where sealcoating does exactly what it claims to do.

Advanced raveling is past that point. Where the surface has lost significant aggregate and is rough throughout, the answer is resurfacing rather than a coating over a deteriorated surface.

Full-depth patching, and why it costs what it costs

A full-depth patch means removing the failed pavement through its full thickness, dealing with the base underneath, and rebuilding the structure in that area.

That is the repair that changes the outcome. A surface patch over a failed base is a cosmetic operation with a known failure date. The cost difference between the two is real, and so is the difference in how long they last.

Done properly, a full-depth patch involves cutting clean vertical edges into sound pavement rather than feathering into broken material, removing everything that has failed, assessing and correcting the base, applying tack to the vertical faces so the patch bonds to the existing pavement, and compacting the new material properly in appropriate lifts.

The edges are where patches fail, and the reason is almost always that they were not cut square into sound material or the vertical faces were not tacked. A patch that is delaminating around its perimeter after one winter was built that way.

Failed patches tell you about the contractor

A lot with multiple failed patches is a lot that has been repaired repeatedly without the cause ever being addressed, and that pattern is worth naming when it appears.

The most common version is a sequence of surface patches over a base that has been failing the whole time. Each one held for a season or two. Collectively they cost more than the correct repair would have, and the underlying area is now larger than it was at the start.

The other common version is patches that were the right idea and were built badly: feathered edges, no tack, poor compaction, or material placed in conditions where it could not compact. These fail at the perimeter and are easy to recognize.

On a property with a repair history like that, the useful step is an assessment that covers the whole lot rather than another round of individual repairs — because the question is no longer what to do about each patch, it is what is happening underneath them.

A sensible order of operations

1. Establish what is causing each defect, distinguishing surface from base.
2. Map where water stands after rain or snowmelt, because that is where the next failures will appear.
3. Correct the drainage where it can be corrected.
4. Rebuild the structurally failed areas full depth, to the specification the loading requires.
5. Seal the cracks that are worth sealing, before winter rather than after it.
6. Resurface or treat the surface only once the structure underneath is sound.
7. Restripe last, on a finished surface.

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