| Length (m) | Cut area 1 (m²) | Cut area 2 (m²) | Fill area 1 (m²) | Fill area 2 (m²) |
|---|---|---|---|---|
| 25 | 14 | 18 | 6 | 7 |
| 30 | 10 | 9 | 8 | 10 |
| 20 | 6 | 4 | 12 | 11 |
1) What cut and fill represents
Cut is material removed from high areas to reach design grades, while fill is material placed in low areas to reach the same target surface. A balanced site aims to minimize import and export, reducing haulage cost and schedule risk.
2) Common workflows on real sites
Early takeoffs often start with a pad or zone using the Area‑Depth method, then evolve to segmented Average End Area estimates along roads, trenches, and retaining wall backfill. Designers typically refine volumes after field survey control is verified.
3) Swell and shrink data points
Excavated soils expand because structure loosens, so loose cut volume can be 10–35% higher than in‑place volume depending on moisture and grading. Placed soils then compact; loose fill required may be 5–20% higher than compacted design volume.
4) Compaction and moisture considerations
Specifications often require relative compaction targets that change by layer type. When moisture is too low, compaction energy is less effective; when too high, pumping and instability can occur. Field density testing and lift thickness control improve predictability.
5) Segments and cross‑sections
The Average End Area method assumes a linear change in cross‑section between stations. Shorter station spacing improves accuracy where terrain varies quickly. If cross‑sections include both cut and fill in one station, separate their areas before computing volumes.
6) Topsoil stripping and unsuitable material
Stripping depth can add meaningful cut volume across large pads. Stripped topsoil is usually stockpiled for later landscaping and should not be mixed into structural fill. Similarly, unsuitable materials may require over‑excavation and replacement, increasing import.
7) Haul planning and truckloads
Truckload estimates help verify access, dumping constraints, and cycle times. Use conservative payload capacities and include bulking. A small volume imbalance can still create many trips, especially for long hauls or limited working hours and traffic windows.
8) Quality checks before issuing numbers
Confirm units, station lengths, and that all areas are non‑negative. Review net loose volume for reasonableness against the site footprint and grade changes. If results look extreme, recheck inputs and consider subdividing the site into smaller zones.
For reporting, record whether volumes are preliminary or issued-for-construction, and note the assumed factors, station spacing, and whether pavements, structures, or utilities were excluded. Many teams add a small contingency, then update after field verification and test results. Keeping assumptions visible makes bid comparisons fair and helps crews align on how the numbers were produced.
1) Which method should I use?
Use Area‑Depth for slabs, building pads, and simple zones with a representative average grade change. Use Average End Area when you have station cross‑sections, such as roads, trenches, channels, or long linear grading features.
2) Why are there in-place and loose volumes?
In‑place volume describes soil in its natural state. Once excavated, soil swells and occupies more space. Loose volume is what you actually haul. The calculator applies swell to cut and shrink/compaction to fill planning volumes.
3) What swell and shrink values are reasonable?
Typical swell ranges about 10–35% and depends on soil type, moisture, and excavation method. Typical shrink/compaction allowance ranges about 5–20%. Use project geotechnical guidance when available and apply conservative values early in design.
4) How does topsoil stripping affect results?
Stripping adds an additional excavation volume across the input area. It increases cut and usually increases export unless topsoil is stockpiled for reuse. If stripping occurs only in part of the site, split the job into separate zones.
5) Can cut material be used as fill?
Often yes, but only if it meets specification for gradation, plasticity, and moisture. Some soils require processing or blending. Unsuitable or organic materials are typically wasted. The net value helps you see whether import is required.
6) Why does station spacing matter in Average End Area?
The method assumes area changes linearly between stations. If terrain changes rapidly, large spacing can miss peaks and valleys and misstate volumes. Reducing station spacing, especially near transitions, improves estimates and reduces construction surprises.
7) Are truckloads exact?
Truckloads are a planning estimate based on your stated capacity and loose net volume. Real loads vary with moisture, material density, equipment limits, and legal payload rules. Add contingency and review haul cycle time for scheduling.
1) Area-Depth method
Compute depth difference: Δz = zproposed − zexisting. Volume equals V = A · |Δz|. If Δz > 0, it is fill; if negative, it is cut.
Optional stripping adds: Vstrip = A · dstrip to cut.
2) Average End Area method
For each segment of length L, compute: V = L · (A1 + A2) / 2. Apply the formula separately for cut areas and fill areas.
Material factors
Loose cut = in-place cut × (1 + swell%). Loose fill required = compacted fill × (1 + shrink%). Net loose volume indicates import or export.
- Select your unit system to match project drawings.
- Choose a method: Area-Depth for pads, segments for corridors.
- Enter swell, shrink, and truck capacity based on material.
- Optionally add stripping depth if topsoil is removed.
- Fill in the method inputs and press Calculate.
- Review net import/export and truckloads for logistics.
- Download CSV or PDF for records, bids, and approvals.
Accurate earthwork estimates reduce costs and prevent delays today.