Reconcile volume at crossing concrete wall segments.
Is an intersection included in both wall segment measurements?
Use the matching calculator
Use this decision sequence
- Define each wall segment’s measured length boundary consistently.
- Calculate gross volume for each segment using its specified thickness and height.
- Identify only the intersection volume included in more than one segment.
- Deduct that duplicated volume once; keep actual openings as separate deductions.
Keep the quantities distinct
| Quantity or assumption | How to use it |
|---|---|
| Centreline segment lengths | Can overlap at intersections. |
| Net end-to-face lengths | May already exclude the overlap. |
| Opening volume | A separate void, not another label for intersection correction. |
Worked comparison
Two illustrative perpendicular segments each include the same 0.2 m by 0.2 m intersection over a 2 m height. Their gross sum counts 0.08 m³ there twice. Deducting 0.08 m³ once leaves the actual union. If the supplied segment lengths already stop at the adjacent face, applying that same deduction again would undercount material.
Check before using the estimate
The deduction must come from the way your plan’s lengths were measured; do not use a generic deduction percentage.
All dimensions, product properties, prices and specifications in this example are illustrative arithmetic inputs. Use the values from your measured plan, selected product data sheet and supplier quote. This guide does not choose construction specifications or certify safety.
Calculation and scope checked 2026-10-04. Methods and scope.
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