Paving & Sitework Calculators
Take a site from bare ground to a finished surface with Paving & Sitework Calculators. Balance cut and fill, check excavation slopes, and estimate asphalt tons. Price gravel, concrete, and paver driveways.
Where Paving & Sitework Calculators Fit
Paving & Sitework Calculators follow the order a site is actually built. Dirt moves first. Slopes get cut and checked. Base goes down. The surface goes on last.
Each stage has its own numbers. A mistake in an early stage carries into every later one. A short fill estimate means extra trucks. A wrong asphalt thickness means a wrong ton order.
1. Moving Dirt
The Cut And Fill Calculator compares what you dig out with what you need to place. The Fill Dirt Calculator sizes the material needed to raise an area. The Excavator Productivity Calculator estimates how much a machine moves per hour, from bucket size and cycle time.
2. Cutting Safe Slopes
The Excavation Slope Calculator works out the side slope and top width of a trench by soil type. The Driveway Slope Calculator checks grade and angle from rise and length, so a driveway drains without being too steep to use.
3. Laying Asphalt
The Asphalt Calculator turns area and thickness into tons. The Asphalt Compaction Calculator finds the loose depth the crew must lay to reach the finished depth. The Asphalt Temperature Calculator checks how fast hot mix cools. The Cold Patch Asphalt Calculator sizes bagged patch for potholes.
4. Pricing the Driveway
Three tools cover the common driveway types. The Gravel Driveway Calculator sizes stone in tons and yards. The Concrete Driveway Cost Calculator estimates concrete and total cost. The Paver Calculator counts pavers, base, and sand.
Run the same driveway through more than one tool. Enter your local prices. That gives a fair side-by-side comparison for your area.
Bank, Loose, and Compacted Soil
Soil has three volumes. Mixing them up is one of the most common earthwork errors.
| State | What it means | Used for |
|---|---|---|
| Bank (BCY) | Undisturbed soil in the ground | Cut volumes from the plans |
| Loose (LCY) | Dug soil with air gaps | Counting truck loads |
| Compacted (CCY) | Soil rolled into place | Fill volumes |
Soil swells when you dig it. Estimators commonly see about 15–30% swell for ordinary soil. Clay and rock can swell more. Sand and gravel usually swell less.
Say you cut 1,000 bank yards with 25% swell. The trucks carry 1,250 loose yards. Count loads from the loose number, not the bank number.
Soil also shrinks when compacted. That means you need more bank yards than the compacted fill volume shown on the plans. Start from bank volume, then apply swell or shrink. Never stack one factor on top of the other.
OSHA Trench Slopes
OSHA Subpart P sets the steepest side slope allowed for excavations up to 20 feet deep. The limit depends on soil type. Slopes are written as horizontal to vertical.
| Soil type | Max slope (H:V) | Angle |
|---|---|---|
| Stable rock | Vertical | 90° |
| Type A | 3/4 : 1 | 53° |
| Type B | 1 : 1 | 45° |
| Type C | 1-1/2 : 1 | 34° |
A 1:1 slope means the wall steps back 1 foot for every foot of depth. So a 10 ft deep trench in Type B soil needs the top edge 10 ft back from the bottom on each side.
Excavations deeper than 20 feet need a sloping or benching design by a registered professional engineer. Soil type must be classified by a competent person on site.
Asphalt Tonnage
Hot mix asphalt is sold by the ton. Most estimates use about 145 lb per cubic foot for compacted hot mix. The actual figure depends on the mix design.
$$\text{Tons} = \frac{\text{Area (sq ft)} \times \text{Thickness (ft)} \times 145}{2000}$$
Take a two-car driveway 20 ft by 24 ft, paved 3 inches thick. That is 480 sq ft × 0.25 ft, or 120 cubic feet. At 145 lb per cubic foot, it comes to about 8.7 tons. With 5% waste, order about 9.1 tons.
| Compacted thickness | Area covered by 1 ton |
|---|---|
| 2 in | About 83 sq ft |
| 3 in | About 55 sq ft |
| 4 in | About 41 sq ft |
Always work from compacted thickness. Hot mix loses depth under the roller. Crews commonly lay it about 20–25% thicker than the finished spec. The compaction tool finds that loose depth for you.
Why Lift Thickness Matters
Hot mix must be compacted before it cools too far. Thin lifts lose heat much faster than thick ones.
One published example uses a 40°F day and mix laid at 250°F. A 3 inch lift took about 19 minutes to cool to 175°F. A 1 inch lift took about 3 minutes.
Wind, cold base, and low sun shrink that window further. Many specs call for air temperature of at least 50°F and rising. Your local spec controls the exact limit.
Common Estimating Mistakes
Counting trucks from bank yards. Dug soil takes more room. Use loose volume for hauling.
Entering loose asphalt depth. Tonnage should come from finished, compacted thickness.
Measuring a slope flat. A sloped surface is longer than its flat run. Measure the real surface for paving and patching.
Skipping the base. Asphalt, concrete, and pavers all need a compacted base. Budget for it separately from the surface.
FAQs
How do I calculate tons of asphalt?
Multiply area in square feet by compacted thickness in feet. Multiply by 145, then divide by 2,000. Add 5–10% for waste.
How much does a ton of asphalt cover?
At 145 lb per cubic foot, one ton covers about 83 sq ft at 2 inches and about 55 sq ft at 3 inches.
What is the difference between swell and shrink?
Swell is the volume gain when soil is dug out. Shrink is the volume loss when it is compacted as fill. Both are measured against the bank volume.
What slope does OSHA allow for a trench?
For excavations up to 20 feet deep, the steepest allowed slope is 3/4:1 in Type A soil, 1:1 in Type B, and 1-1/2:1 in Type C.
Can asphalt be laid in cold weather?
It is harder, because the mix cools before it can be compacted. Thicker lifts and hotter mix buy more time. Many specs require at least 50°F and rising.
Are these results enough for permits or safety plans?
They are for planning and ordering. Trench protection, pavement design, and grading plans must follow local code. Have them checked by a competent person or engineer.