BagsAndYards How much you need — and what it costs

Concrete for a 12×14 slab

A 12×14 ft slab at 4″ thick needs about 103 × 80 lb bags of concrete mix (with 10% waste) — or 2.5 cubic yards of ready-mix. Estimated materials cost ≈ $413 (ready-mix).

Volume56 ft³ = 2.07 cu yd
80 lb bags (no waste)94
80 lb bags (10% waste)103
60 lb bags (10% waste)137
Ready-mix2.5 cu yd
RecommendedOrder ready-mix

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Estimated materials cost

Estimate for standard concrete mix (e.g. Quikrete #1101 / Sakrete High-Strength). Bag counts round up and include your overage %. Cost is an estimate (as of June 2026, US national average) — confirm bag price and ready-mix delivery (often a 1 yd³ minimum + short-load fees) with your supplier. Not a substitute for a structural engineer on load-bearing work.

Last updated: 2026-06-28.
Bag yields from the QUIKRETE #1101 data sheet. Cost figures are US-national-average estimates and vary by region and supplier.