Tar and Chip Driveway Calculator
Enter your driveway’s length and width, choose a single or double chip seal layer, and pick a chip stone type to see the tons you need.
Measure straight across the widest point.
Adjust depth below if needed.
Covers spillage and compaction. 5–10% is normal.
Everything is calculated in your browser. Nothing you type is sent anywhere or stored.
Bags or bulk delivery?
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Coverage & weight
Material profile
For the calculator’s default 60 ft × 12 ft driveway with a single 0.5-inch chip seal layer, you’ll need about 1.22 cubic yards, or roughly 1.75 tons of pea gravel chip stone including a 10% waste allowance. That’s around 66 bags if you’re buying a small touch-up quantity by the bag.
Chip stone needed for common tar-and-chip driveway sizes
These estimates use pea gravel chip stone at 2,700 lb per cubic yard with a 10% waste allowance built in.
| Project | Depth | Cubic yards | Tons |
|---|---|---|---|
| Single-car driveway, 360 sq ft | 0.5 in | 0.61 yd³ | 0.83 tons |
| Double-car driveway, 900 sq ft | 0.5 in | 1.53 yd³ | 2.06 tons |
| Long driveway, double layer, 1,200 sq ft | 0.75 in | 3.06 yd³ | 4.12 tons |
| Rural driveway, double layer, 2,400 sq ft | 0.75 in | 6.11 yd³ | 8.25 tons |
| Driveway with turnaround, 600 sq ft | 0.5 in | 1.02 yd³ | 1.38 tons |
Chip stone types, size and traction
| Type | Weight per yd³ | Best for | Drainage |
|---|---|---|---|
| Pea gravel chip stone (3/8in) | 2,700 lb | Standard tar-and-chip topcoat | Good |
| Trap rock chip stone (3/8in) | 2,800 lb | Higher-traction chip seal | Good |
Figures are for dry material. Wet or freshly delivered material can weigh noticeably more.
How to calculate chip seal aggregate you need
- Measure the driveway length × width in feet, including any turnaround or apron areas.
- Pick single or double layer 0.5in for a standard single chip seal, 0.75in for a fuller double layer.
- Convert to cubic yards multiply area by depth in feet to get cubic feet, then divide by 27.
- Add waste add about 10% for stone that scatters off the shoulders during rolling and traffic.
- Convert to tons multiply cubic yards by the stone’s density (about 2,700-2,800 lb/yd³) and divide by 2,000.
Worked example
Using the calculator’s default 60 ft × 12 ft driveway with a single 0.5-inch chip seal layer of pea gravel chip stone:
- Area60 ft × 12 ft = 720 sq ft
- Depth in feet0.5 in ÷ 12 = 0.042 ft
- Volume720 sq ft × 0.042 ft = 30 cu ft
- Plus 10% waste30 × 1.10 = 33 cu ft
- Cubic yards33 ÷ 27 = 1.22 yd³
- Weight (pea gravel chip stone, 2,700 lb/yd³)1.22 × 2,700 = 3,300 lb
- Tons3,300 ÷ 2,000 = 1.65 tons
- Order amountround up to 1.75 tons, or about 66 bags at 0.5 cu ft each
Recommended depth by project
| Project | Recommended depth | Notes |
|---|---|---|
| Single chip seal layer | 0.5 in | Standard residential tar-and-chip topcoat |
| Double chip seal layer | 0.75 in | Extra durability and a fuller, denser stone look |
| Touch-up / resealing | 0.25-0.375 in | Refreshing an existing chip seal surface |
| Steep or high-traffic drive | 0.75-1 in | More stone embedment for better grip and wear |
| Shared or commercial drive | 1 in+ | Heavier stone coverage for repeated vehicle loads |
Bags or bulk delivery?
Bagged chip stone is really only practical for patching a worn spot or touching up a chipped edge. A full driveway needs the stone spread and rolled while the asphalt emulsion binder underneath is still tacky, which is a bulk-delivery, whole-driveway job rather than a bag-at-a-time one.
- Small touch-upsunder 1 ton — bags are fine for patching bare or worn spots between resealing cycles.
- Medium driveways1 to 4 tons — compare bag cost against bulk price plus delivery, but bulk usually wins.
- Full drivewaysover 4 tons — always order bulk; the chip seal contractor applies it while the binder is still tacky.
Common mistakes
- Forgetting the emulsion binderthis calculator sizes the chip stone topcoat only — you’ll also need to budget for the hot asphalt emulsion (“tar”) sprayed underneath it.
- Applying chips too thina layer thinner than about 3/8in leaves gaps where the binder shows through and wears unevenly.
- Skipping the roller passchip stone must be rolled into the emulsion right after spreading, or loose stone scatters and the seal doesn’t bond properly.
- Chip-and-sealing over a cracked basetar and chip is a thin wearing surface, not a structural repair — cracks and potholes in the base telegraph through within a season or two.
- Not sweeping loose stoneexcess loose chip left on the surface after rolling gets tracked onto lawns and into garages for weeks if it isn’t swept off.
- Underestimating driveway edges and apronsmeasuring only the main straight run and forgetting the street apron or turnaround leads to running short mid-job.
What this calculator assumes
Adjust your result if your project differs from these.
- Depth is the finished chip stone layer thickness, not including the emulsion binder underneath.
- Density assumes standard pea gravel or trap rock chip stone at typical bulk density.
- 10% waste covers stone that scatters during rolling and initial traffic before it locks in.
- Prices are for chip stone only; the asphalt emulsion binder and application labor are separate.
- The existing base (asphalt, compacted gravel, or oil-and-stone) is assumed sound before chip sealing.
- Bag coverage assumes 0.5 cu ft bags; bulk delivery is standard for a full driveway.
Common questions
How much chip stone do I need for a tar and chip driveway?
For the calculator’s default 720 sq ft single-layer driveway, you’ll need about 1.22 cubic yards, or roughly 1.75 tons of chip stone.
What's the difference between single and double chip seal?
A single layer (about 0.5in) is the standard residential application; a double layer (about 0.75in) uses more stone for a fuller look and extra wear life.
Does this calculator include the tar/emulsion cost?
No — it calculates the chip stone topcoat only. The asphalt emulsion binder sprayed underneath is priced and ordered separately, usually by the contractor.
How long does a tar and chip driveway last?
Typically 7-10 years before it needs a fresh chip seal, versus 15-20+ years for hot mix asphalt, but it costs less per application.
What kind of stone is used for tar and chip?
Small, uniform stone in the 3/8in range — pea gravel for a smoother look, or angular trap rock for better traction.
Can I do tar and chip as a DIY project?
It’s possible on a small scale, but the hot emulsion and correctly timed rolling are hard to manage without contractor equipment — most homeowners hire this out.
How much does a tar and chip driveway cost?
For the default 720 sq ft example, expect roughly $184 in chip stone material alone; total installed cost including the emulsion and labor runs several times that.
Does tar and chip need to be resealed?
Yes — plan on a fresh chip seal application every 7-10 years to keep the surface bound and prevent loose stone.
Is tar and chip cheaper than asphalt?
Yes, tar and chip is typically 20-40% cheaper to install than hot mix asphalt, though it needs more frequent resealing.
Can tar and chip go over an existing gravel driveway?
Yes, a compacted gravel base is a common and suitable substrate for a tar-and-chip topcoat, as long as it’s well-graded and stable.
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Project
| Shape | — |
| Dimensions | — |
| Depth | — |
| Area | — |
| Material | — |
| Waste allowance | — |
Volume & weight (incl. waste)
| Cubic yards | — |
| Cubic feet | — |
| Weight | — |
| Tons (rounded up) | — |
Shopping list
| Bulk order | — |
| Bagged alternative (0.5 cu ft) | — |
| Estimated cost | — |
Notes
Estimate generated by materialcalculate.com. Assumes uniform depth and standard dry material densities. Confirm quantities with your supplier before ordering.