The Differences Between Cold Patch vs Hot Mix Asphalt
Cold patch asphalt is a ready-to-use mix you tamp into a pothole in any weather, but it's a temporary repair. Hot mix asphalt is made at a plant, leaves it at about 300°F and gets rolled tight, and it's the repair that lasts. The differences between cold patch vs hot mix asphalt come down to the season and how long the fix has to hold.
Around Pittsburgh and the surrounding counties, most homeowners end up using both. A bag of cold patch gets a driveway through February. A hot patch or a bigger repair follows once the plants reopen and the ground warms up. If the same hole keeps coming back, the problem is under the pavement, and neither patch will fix it alone.
What Is Cold Patch Asphalt?
Cold patch asphalt is crushed stone coated with an asphalt binder that has been thinned so it stays soft at outdoor temperatures. Hardware stores sell it in bags and buckets, and some brands come in pails with a resealable lid. You pour it into the hole, pack it down and drive on it. Nothing gets heated.
The softness that makes it easy to use is also its weak spot. Cold patch firms up slowly as the thinners evaporate and traffic packs it. It never gets as dense or as tightly bonded as hot mix. Water, plow blades and tires work at it until the edges loosen and the patch pops out.
What Is Hot Mix Asphalt?
Hot mix asphalt is the same material a driveway or road is built from. It comes from an asphalt plant, where stone and sand are heated and coated with liquid asphalt. It has to be placed and compacted while it's still hot. As it cools, the stone and binder lock together into solid pavement.
A good hot patch also bonds to the old asphalt around it. The crew cuts the damaged area square, coats the edges with a tack coat and fills the hole with hot mix. Tack coat is a thin spray of liquid asphalt that glues new asphalt to old. Once it's rolled, the patch carries weight the same way the rest of the pavement does. Our guide to what asphalt is made of and how it's laid explains why heat and compaction matter so much.
Is Cold Patch Asphalt Any Good?
Cold patch asphalt is good for holding a hole until a permanent repair can be made. It fills the hole the same day, works in freezing weather and needs only a tamper. For a pothole that's eating tires in January, that's exactly what you need.
It's a poor choice as the final fix. A cold patch sits on top of the problem without sealing the edges, so water keeps working at the base underneath. How well it holds depends far more on prep and compaction than on the brand you buy.
How Long Does Cold Patch Asphalt Last?
In winter, most cold patches don't last long. A field survey in the Transportation Research Record found that about 70% of throw-and-roll cold patches lasted less than 14 months. Patches put in during winter broke down fastest, mostly from freezing weather and poor compaction. Patches that made it through their first winter were usually packed tight and fully cured, and those tended to last much longer.
So how you put it in matters about as much as which bag you buy. A dry hole and hard compaction can buy you a full season. A loose fill dropped into standing water may not last a week of plowing.
A hot asphalt patch done right, with a sound base under it, usually lasts as long as the pavement around it.
When Cold Patch Makes Sense
Cold patch earns its spot in the garage. Reach for it when:
It's winter and hot asphalt isn't available
The hole is a tripping hazard or is eating tires and can't wait
You plan a proper repair once the weather warms up
The driveway is due for replacement soon and only has to get through one more season
If none of those fit, skip the bag and plan a hot patch.
How to Use Cold Patch Asphalt
A few minutes of prep makes a cold patch last much longer:
Clear out loose stone, dirt and as much water as you can. A shop vac or old towels help.
Pour in cold patch until it's mounded slightly above the driveway surface.
Pack it hard with a hand tamper, or drive a car tire over it several times.
Check that the top is crowned a little, so it settles flat under traffic.
Add more and pack it again if it sinks after a few days.
Holes deeper than a couple of inches hold better when you fill and tamp them in layers. Keep the bag closed between uses and store it where it won't freeze solid. Cold mix that has stiffened is harder to compact.
How a Hot Asphalt Patch Is Done
A hot patch is a small paving job. Here's how a crew handles one:
Saw cut the damaged area into a clean square or rectangle.
Remove the broken asphalt and check the stone base underneath.
Dig out and rebuild the base if it's soft or washed out.
Spray a tack coat on the cut edges so the new asphalt bonds to the old.
Fill with hot mix and compact it with a roller or plate compactor.
Step 3 is where most of the value sits. A hot patch over a wet, soft base will fail the same way the old pavement did.
Why Hot Asphalt Is Hard to Get in Winter
Hot mix ships from the plant at roughly 300°F and starts cooling the minute it's dumped. On frozen ground, it loses heat fast. A small patch can cool before it's rolled tight, and a patch that isn't dense won't hold up.
Supply is the other problem. Many asphalt plants in cold-winter states shut down for part of the winter. That's why winter is cold patch season, and spring is when permanent repairs get scheduled.
Want a spring repair lined up before the rush? Request a free estimate and we'll look at the holes and the base around them.
Why Do Potholes Keep Coming Back?
A pothole that returns in the same spot is a symptom. Water is usually getting under the asphalt and softening the base. Each freeze pushes the pavement up, and each thaw leaves a weaker spot for tires to break.
Look around the hole for these signs:
Spiderweb cracking spreading out from the patch
Spots that feel soft or sink when you drive over them
Water that pools or runs across the driveway after a rain
Several potholes in the same area
Those point to a base or drainage problem that no patch will fix. Read when to replace an asphalt driveway to see which signs mean the base has given out. Sometimes the answer is rebuilding one section of base work instead of repaving everything.
Which Costs Less Over Time?
A bag of cold patch is the cheapest fix on the day you do it. Over a few winters, the math often flips. Most of what any patch costs is the time it takes to do it, and a cold patch that has to be redone every spring keeps adding that time back.
A hot patch costs more up front because it needs hot mix, a saw and a crew. When the base under it is sound, you pay for it once. If you're patching the same driveway every year, compare that with what a proper repair or residential asphalt paving would cost before buying more bags.
Cold Patch vs Hot Mix Asphalt Side by Side
Cold patch | Hot mix asphalt | |
How long it lasts | Weeks to months, sometimes longer if packed well | Years, often as long as the pavement around it |
Season | Any season, including winter | Warm months, when plants are open and the ground isn't frozen |
Who puts it in | Homeowner or maintenance crew | Paving crew with hot mix and a roller or plate compactor |
Prep | Clear out debris and water, then fill | Saw cut, remove broken asphalt, fix the base, tack the edges |
Bond to the old pavement | Mostly sits in the hole | Bonds to clean, tacked edges |
Cost on the day | Lowest | Higher |
Best use | Holding a hole until spring | Fixing the hole for good |
Can You Use Cold Patch on a Parking Lot?
Cold patch works on a parking lot as a stopgap. Property managers keep cold patch on hand because a pothole near an entrance is a trip and liability risk. Fill it the same day, mark it if needed and schedule a hot repair for spring.
On a lot with truck traffic, cold patch wears out faster. Delivery trucks and plows shove the soft mix out of the hole. Expect to check those patches after every storm. Our commercial paving page covers parking lot repair and the night and weekend work that keeps a lot open.
Frequently Asked Questions
Which is better, cold patch or hot patch?
Hot patch is better for a lasting repair because it's compacted hot and bonds to the pavement around it. Cold patch is better when you need the hole filled today, in cold weather, without equipment.
Can you put cold patch over existing asphalt?
Cold patch belongs inside the hole. A thin layer spread over sound asphalt won't stick and will flake off under tires. Fill the hole, mound it slightly and pack it level with the pavement around it.
Can you use cold patch in the winter?
You can. Cold patch is made for cold weather. Clear out water and loose material, overfill the hole and pack it hard. Plan a permanent hot repair once the weather warms up.
Can you put hot asphalt over cold patch?
It's better to remove the cold patch first. A proper hot patch cuts out the old material so the new asphalt bonds to solid pavement on every side.
How long before you can drive on cold patch?
You can drive on it right away. Driving over a fresh cold patch helps compact it. Go slowly the first few times, and add more mix if it sinks.
Does cold patch work in a wet hole?
It works better in a dry one. Standing water keeps the mix from packing tight and bonding to the sides. Sweep or soak out as much water as you can before filling.
Can you use cold patch asphalt on concrete?
It works only as a short-term fill. Asphalt cold patch doesn't bond well to concrete and stands out against it. A crack or hole in a concrete driveway lasts longer when it's repaired with a concrete patching product.
Can I patch my driveway with hot asphalt myself?
Small holes are fine for cold patch, but hot patching is a crew job. It takes hot mix from a plant, a saw, a tack coat and compaction equipment, all used before the mix cools.
Get the Holes Fixed for Good
We've patched, rebuilt and paved driveways and parking lots for over 50 years from our family shop in Latrobe. Our crews work in and all around Pittsburgh and across Westmoreland, Washington, Butler and Indiana Counties.
Still weighing cold patch vs hot mix asphalt for a hole in your driveway or lot? We'll find out why it keeps opening up and show you what a lasting repair takes. Estimates are free.
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