Multi Box Culvert Quantities Calculator
Browse every culvert on one at a time — barrel, wing wall, apron slab, toe wall, loose riprap and mortared riprap quantities — priced against editable unit rates, plus a live project-wide total.
Unit Rates
Culvert Browser
Quantity & Cost Summary
Barrel — geometry & quantities
Wing Wall (4 no., both ends)
Apron Slab (both ends)
Toe Wall (both ends)
Loose Riprap Class C & Mortared Riprap Class B (both ends)
Project Totals — All 266 Culverts
About this box culvert quantities calculator
This tool prepares a bill of quantities and cost estimate for the box culverts on a road project. It is aimed at highway and drainage engineers, quantity surveyors and estimators who need structure quantities during detailed design, tender preparation or cost checking. Each culvert is derived from its barrel dimensions and standard headwall geometry — parapets, wing walls, aprons and toe walls — and priced against unit rates you control.
What it calculates
- Structural excavation, in cubic metres
- Class A3 concrete, split into underground, on ground and elevated pours
- Lean concrete blinding
- Reinforcing steel, by weight in tons
- Loose riprap Class C for scour protection
- Mortared riprap Class B, plus the filter material beneath it
What you control
Every unit rate is editable, along with the contingency percentage, currency label and the number of decimal places shown. Change any rate and both the selected culvert and the project-wide total recalculate immediately. Results can be copied for a single culvert or downloaded as a full project BOQ in CSV, ready for Excel.
How to read the output
The summary table lists each pay item against its BOQ reference, quantity, unit, rate and cost. Open the detailed breakdown to see the underlying geometry and quantities for the barrel, the four wing walls, the apron slabs, the toe walls and the riprap at both ends. The project totals card at the foot of the page aggregates every culvert in the dataset.
Frequently asked questions
What does the multi box culvert quantities calculator do?
It produces a bill of quantities and cost estimate for every box culvert on a road project. You browse the culverts one at a time and see barrel, wing wall, apron slab, toe wall and riprap quantities, each priced against your own unit rates, alongside a live project-wide total.
Which quantities does the box culvert calculator compute?
Structural excavation, Class A3 concrete split into underground, on ground and elevated, lean concrete, reinforcing steel by weight, loose riprap Class C, mortared riprap Class B, and filter material under the mortared riprap.
How are box culvert construction costs calculated?
Each quantity is multiplied by the unit rate you enter for that item, then a contingency percentage is applied on top. Rates, currency, contingency and decimal places are all editable, so the output matches your own schedule of rates.
Can I export the culvert bill of quantities?
Yes. You can copy the currently selected culvert as CSV, or download the full project bill of quantities for all culverts as a CSV file that opens directly in Excel.
What is the difference between loose riprap Class C and mortared riprap Class B?
Loose riprap Class C is dry-placed stone used for general scour protection around the culvert. Mortared riprap Class B is grouted stone used where higher velocities demand a bound surface, and it is laid over a filter layer, which this calculator quantifies separately.
Can I change the currency and unit rates?
Yes. Every unit rate is an editable field, and the currency label defaults to PKR but accepts any code you type. All per-culvert results and the project total recalculate immediately.
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