Fidamen

Concrete Trench Volume Calculator

This calculator estimates the concrete required to fill rectangular trenches. Enter trench dimensions in metres, set the number of identical trenches, and include an allowance for waste. Outputs include volume in cubic metres, cubic yards, and cubic feet, an estimated mass using standard concrete density, and an estimate of ready-mix truck loads.

The tool assumes rectangular cross-sections. For trapezoidal or v-shaped trenches, use the average width across the depth or consult an engineer for precise excavation shapes. Values are approximate; final ordering should be confirmed with site measurements and supplier guidance.

Updated Nov 2, 2025QA PASS — golden 25 / edge 120Run golden-edge-2026-01-23

Governance

Record 5b6bc18216dc • Reviewed by Fidamen Standards Committee

Inputs

Results

Updates as you type

Required concrete volume (m³)

0.99

Required concrete volume (yd³)

1.2949

Required concrete volume (ft³)

34.9615

Estimated concrete mass (kg)

2,376

Ready-mix trucks required

0.1238

OutputValueUnit
Required concrete volume (m³)0.99m³
Required concrete volume (yd³)1.2949yd³
Required concrete volume (ft³)34.9615ft³
Estimated concrete mass (kg)2,376kg
Ready-mix trucks required0.1238—
Primary result0.99

Visualization

Methodology

Primary volume is computed with the standard prismatic formula: length × width × depth per trench, multiplied by the number of trenches and increased by the user-specified waste allowance.

Conversions use standard SI relationships: 1 m³ = 1.30795062 yd³ and 1 m³ = 35.3146667 ft³. Estimated mass uses a nominal concrete density of 2400 kg/m³ (typical for normal-weight concrete).

Ready-mix truck counts are an estimate dividing required volume by the user-supplied typical truck capacity (m³). Round up physical orders to account for staging, return, and minimum dispatch sizes when placing an order with a supplier.

F.A.Q.

Can I use this calculator with imperial measurements (feet/inches)?

This calculator accepts metres for dimensions. To use feet, convert values to metres first (1 ft = 0.3048 m). For convenience, multiply feet measurements by 0.3048 before entering them.

What waste allowance should I use?

A common practice is 5–10% for straightforward pours and 10–15% for complex sites or deeper trenches. Increase allowance for inaccurate site dimensions, spillage, or extended pumping lines.

Why does the tool use 2400 kg/m³ for mass estimates?

2400 kg/m³ is a commonly used nominal density for normal-weight concrete used in many engineering references. Actual density varies with mix design and aggregates; use supplier data for precise mass calculations.

Does the calculator consider reinforcement (rebar) displacement?

No. Reinforcement typically displaces a small concrete volume; for heavy reinforcement or close tolerances, subtract the estimated rebar volume or consult a structural engineer for precise ordering.

Are there safety or regulatory considerations for trenches?

Yes. Trenching and excavation carry hazards including collapse, confined spaces, and utility strikes. Follow local regulations and guidance such as occupational safety authorities' trenching and excavation standards before working in trenches.

Sources & citations

Further resources

Versioning & Change Control

Audit record (versions, QA runs, reviewer sign-off, and evidence).

Record ID: 5b6bc18216dc

What changed (latest)

v1.0.0 • 2025-11-02 • MINOR

Initial publication and governance baseline.

Why: Published with reviewed formulas, unit definitions, and UX controls.

Public QA status

PASS — golden 25 + edge 120

Last run: 2026-01-23 • Run: golden-edge-2026-01-23

Engine

v1.0.0

Data

Baseline (no external datasets)

Content

v1.0.0

UI

v1.0.0

Governance

Last updated: Nov 2, 2025

Reviewed by: Fidamen Standards Committee (Review board)

Credentials: Internal QA

Risk level: low

Reviewer profile (entity)

Fidamen Standards Committee

Review board

Internal QA

Entity ID: https://fidamen.com/reviewers/fidamen-standards-committee#person

Semantic versioning

  • MAJOR: Calculation outputs can change for the same inputs (formula, rounding policy, assumptions).
  • MINOR: New features or fields that do not change existing outputs for the same inputs.
  • PATCH: Bug fixes, copy edits, or accessibility changes that do not change intended outputs except for previously incorrect cases.

Review protocol

  • Verify formulas and unit definitions against primary standards or datasets.
  • Run golden-case regression suite and edge-case suite.
  • Record reviewer sign-off with credentials and scope.
  • Document assumptions, limitations, and jurisdiction applicability.

Assumptions & limitations

  • Uses exact unit definitions from the Fidamen conversion library.
  • Internal calculations use double precision; display rounding follows the unit's configured decimal places.
  • Not a substitute for calibrated instruments in regulated contexts.
  • Jurisdiction-specific rules may require official guidance.

Change log

v1.0.0 • 2025-11-02 • MINOR

Initial publication and governance baseline.

Why: Published with reviewed formulas, unit definitions, and UX controls.

Areas: engine, content, ui • Reviewer: Fidamen Standards Committee • Entry ID: d530249b6b0b