How to Get Cold Patch Asphalt to Harden

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Things You'll Need

  • Gravel

  • Hair dryer

  • Extension cord

  • Cold patch asphalt

  • Metal tamper or lumber

Cold patch asphalt can be a permanent repair but needs time to cure.

The easiest way for a homeowner to quickly and economically repair most small holes that can occur in an asphalt surface is with cold patch asphalt. This material can be poured directly into the area in need of repair and, if done properly, will eventually harden into a permanent repair. The actual material cures from contact with the air, so after properly compacting the patch, it takes time for it to completely harden. This allows the material to flow more readily into small spaces around the hole and makes for a more permanent repair. If you need your patch to cure faster, you can try a few things.

Step 1

Fill the hole to within 2 inches of the top with gravel. Tamp down the gravel thoroughly with a metal tamper or piece of lumber. Add more gravel as needed, continuing to compact it to within 2 inches of the top of the hole.

Step 2

Pour the cold patch asphalt material over the gravel to about 1/2 inch over the top of the hole. Tamp down the patch thoroughly. Add more material as needed, continuing to compact till even with the surface.

Step 3

Plug the hair dryer into the extension cord. Operate the hair dryer in a sweeping motion. Blow hot air over the patch until you cannot easily press into the material. Keep blowing as long as it takes to harden the patch, since it is mostly the air flow that cures it faster.


Preheat the product to make it easier to work with and more adhesive.

Avoid resting anything heavy on the patch that might pierce it before it has cured, such as a motorcycle kickstand or another object where the weight is not distributed properly.

Do not use a sealer or resurfacing product until the patch is completely hardened.


Keep the cold patch asphalt material from contacting your skin or clothing.


Billy Ray

Billy Ray has been writing since 1994. He writes a popular featured column on the sports Web site Bleacher Report and has been licensed in loan origination and real estate. He is an EPA-certified Lead-based-paint renovator. Billy has taken courses in real estate, commercial lending and home renovation in addition to college courses in writing at Southern Oregon State University.