Net volume is not the final order
The construction workflow handles equal rectangular slabs measured in feet, with depth in inches. It does not determine a structurally safe slab thickness, reinforcement, strength class, base preparation or compliance with local requirements.
Work from measured dimensions
Net cubic feet = length × width × (depth in inches / 12) × quantity. Divide by 27 for cubic yards. Multiply the net quantity by 1 + waste percent / 100 for the allowance. Use supplier information for minimum orders, increments, prices and bag yield; the example values are editable assumptions. Unit conversion references: NIST conversion factors.
A checkable synthetic order
One 12 ft × 10 ft slab at 4 in depth uses 40 ft³ net. A 10% allowance gives 44 ft³, or 1.62963 yd³ before ordering rules. A 0.25 yd³ increment rounds this to 1.75 yd³; a 2 yd³ supplier minimum raises the final order to 2 yd³. At $150/yd³, plus $60 delivery and $120 labor, the modeled estimate is $480 before tax and excluded work.
Bagged mix is an alternative, not another item on the same bill
At assumed yields of 0.45 ft³ per 60 lb bag and 0.60 ft³ per 80 lb bag, 44 ft³ needs 98 or 74 bags respectively, rounded up. Confirm the actual product yield. Bag counts use the allowance volume; ready-mix minimum-order rounding does not inflate the alternative bag calculation. Choose one supply method rather than adding both together.
Check exclusions before requesting a quote
The estimate separates material, delivery and labor, but excludes sales tax, permits, excavation, formwork, reinforcement, pumping, difficult access, disposal and supplier-specific surcharges unless you account for them separately. Prices are entered by you, not live quotations.
Keep the audit trail
Save the project, then export it and its report before clearing browser data. The workflow's final volume check is for one slab; multiply by the quantity to compare with total net volume. Recalculate later steps after changing earlier dimensions.
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Continue with the free workflow
The connected construction estimate keeps measurements and entered costs together in a browser-local project. No paid planning pack is offered while checkout is disabled.