How to use it
- Enter length, width, and thickness.
- Click Calculate.
- Read cubic yards, bags, and cubic feet results.
What it does – The calculator turns the dimensions of your shed foundation into three practical measures: cubic yards (what most suppliers quote), total bags of 80‑lb mix, and cubic feet (useful for on‑site checks).
Why it matters – Ordering too little means delays; ordering too much wastes money and space. By seeing all three units you can compare supplier quotes, plan deliveries, and verify the job as you pour.
How to read the numbers – Cubic yards = total cubic feet ÷ 27. Bags = cubic feet ÷ 0.6 (each bag gives 0.6 ft³). For example, a 10 × 10 ft slab 4 in thick equals 33.3 ft³, which is 1.23 yd³ and about 56 bags. Use the results to place an accurate order and keep a small excess for spillage.
Pro tips
- Add 5‑10% extra for waste.
- Round up bag count to the next whole bag.
- Order bags in full pallets when possible to reduce shipping.
- Double‑check thickness conversion (inches to feet) before entering.
Real-life examples
- Homeowner building a 12 × 12 ft shed and needs concrete for the floor slab.
- Contractor estimating material for a small garden shed base on a job site.
- DIY enthusiast planning a shed addition and wants to compare supplier prices.
Case study
Mike entered his 10 × 10 ft shed base, 4 in thick, got 1.23 yd³ and 56 bags, ordered that amount, and finished the floor without a single stop‑and‑go to the supplier.