Earthwork Takeoff:
Cut, Fill, and Cubic Yards

Calculate volume

The two workhorses of earthwork volume calculation are the average end area method and the grid method. The average end area method computes volume between two cross-sections as V = (A1 + A2) / 2 × L, where A1 and A2 are the cross-sectional areas at each station and L is the distance between them. Repeat this calculation across every station interval along the alignment, then sum to get total cut and total fill in cubic yards (Solvebility / GX Contractor, 2025).

The grid method is better suited to grading plans without a linear alignment. You overlay a regular grid on the site, read existing and proposed elevations at each grid node, and compute the volume of each vertical prism from the difference. Summing all prisms gives you the total cut and fill by grid cell. Both methods yield the same fundamental output — cubic yards of material that must be removed or placed — and both feed directly into truck load calculations and cost line items.

• Average end area: V = (A1 + A2)/2 × L between cross-sections
• Grid method: volume from elevation differences at grid points
• Both yield cut and fill in cubic yards by station or grid cell

Bank, loose, and compacted yards

Every cubic yard of earthwork exists in one of three states, and confusing them is the single most common — and most expensive — estimating error in sitework. Bank cubic yards (BCY) are soil in its natural, undisturbed state in the ground. Loose cubic yards (LCY) are what that same soil becomes once you excavate and load it into a truck: it swells because air voids open up between particles. Compacted cubic yards (CCY) describe the material after it has been placed and mechanically compacted as fill.

The practical consequence is this: truck hauling is always priced in loose yards, not bank yards. If you quote a haul quantity in BCY and your subcontractor prices in LCY, you will underbid the haul cost by 10–40% depending on soil type. Likewise, if your fill spec requires a certain CCY volume, you need to work backward through the shrink factor to determine how many BCY of cut you can use as fill — and whether there is enough on site.

Apply swell factor

When you cut soil out of the ground, it expands. The swell factor expresses how much. Published industry ranges vary by soil classification: sand and gravel swell 10–20%, loam 20–30%, clay 30–40%, and rock 40–70% (GX Contractor / TCL Consulting, 2025). In practice, a typical assumed swell factor of 25% is used when the soil profile is mixed or unknown — meaning 1 BCY becomes 1.25 LCY once excavated (TCL Consulting, 2025).

Swell directly sets the number of truck loads required. If you have 10,000 BCY of cut and a 25% swell factor, you are hauling 12,500 LCY. At 14 LCY per truck, that is roughly 893 loads rather than 714. The difference in haul cost is not marginal. Always apply swell before pricing haulage, and use site-specific geotechnical data whenever a soil report is available rather than defaulting to 25%.

• Sand/gravel: 10–20% swell
• Loam: 20–30% swell
• Clay: 30–40% swell
• Rock: 40–70% swell
• Typical assumed swell: 25% (1 BCY = 1.25 LCY)

Apply shrink factor

Shrink is the mirror image of swell. When excavated material is placed as structural fill and compacted, it densifies — occupying less volume than it did in its loose state. The shrink factor for compacted fill is typically 0.85–0.95, meaning 1 cubic yard of in-place cut becomes approximately 0.85–0.95 cubic yard of compacted fill (TCL Consulting, 2025). Put another way, you need more cut than fill volume to close a deficit, because compaction consumes material.

The calculation runs in reverse from fill to source: if your design requires 8,000 CCY of fill, and your shrink factor is 0.90, you need 8,000 / 0.90 ≈ 8,889 BCY of cut to supply it. Topsoil stripping and any material classified as unsuitable for structural fill should be tracked separately — these quantities go to waste or spoil disposal and cannot be used to satisfy fill requirements regardless of shrink factor.

• Typical shrink factor: 0.85–0.95 (1 BCY of cut → 0.85–0.95 CCY of fill)
• Convert fill required in CCY back to BCY to determine source volume
• Track topsoil strip and unsuitable material separately from structural fill

Balance the site

Once you have total cut in BCY and total fill requirement in BCY (after back-converting from CCY via shrink factor), the comparison tells you whether the site is in balance. If cut exceeds fill, you have surplus material to export. If fill exceeds cut, you must import borrow. Either condition has a direct cost: export means extra haul trips to a spoil site, import means purchasing and hauling fill material from a borrow pit.

Preliminary earthwork accuracy is typically ±10–15%, reflecting the inherent uncertainty in reading existing contours and predicting soil behavior before detailed grading design is complete (Solvebility / GX Contractor, 2025). A 10–15% contingency on earthwork volume is standard practice at the budgeting stage. Apply the contingency to whichever side is larger — if you are net importing, add contingency to the import quantity; if net exporting, add to the export haul.

• Compare total cut (BCY) to total fill need (BCY) to find net import or export
• Balancing cut and fill on site eliminates haul costs in both directions
• Preliminary accuracy ±10–15%; add 10–15% contingency at budget stage

Questions estimators actually ask