Instantly estimate footing depth, diameter, concrete volume, cubic yards, and bag counts for safety and security bollards in US units — before you call the ready-mix truck or buy bags.
Enter bollard footing dimensions to calculate concrete volume, cubic yards, and bag counts.
Use this for embedded steel pipe bollards set in individual concrete footings.
Choose bag size if you plan to pour from premixed bags.
Common shallow bollard footings are 18–36 in deep.
A typical guide is 3× bollard pipe diameter or more.
Total posts using the same footing size and depth.
A concrete bollard footing is a localized pier or pad of reinforced concrete that anchors a steel or concrete bollard in place below grade so it can resist vehicle contact, impact, and long‑term corrosion. The footing is typically deeper and wider than the bollard itself, allowing the surrounding concrete and soil to share the load instead of relying on the pipe alone.
The amount of concrete you need depends on four main factors: footing depth, footing diameter (or width for a square pier), the number of bollards, and the waste factor you choose for excavation irregularities and spillage. For small projects, premixed bags are convenient, while longer bollard lines or higher‑impact systems are usually poured from ready‑mix trucks using standard US footing practices.
A single round bollard footing with a 16 in diameter and 30 in depth is roughly 3.5–3.7 cubic feet of concrete. Multiply by the number of bollards and then divide by 27 to convert to cubic yards, and always add at least 10% overage so you are not short at the bottom of the excavation.
Many light‑duty storefront or parking lot bollards use individual footings in the 18–30 in depth range with diameters around 12–18 in, depending on bollard size and soil conditions. For true crash‑rated systems, always follow the engineered foundation details provided by the manufacturer.
For typical non‑crash‑rated bollards around commercial buildings, a concrete mix in the 3000–4000 PSI range is common, using normal‑weight aggregate and air entrainment where freeze–thaw exposure exists. Stronger mixes or special designs may be required for certified impact‑resistant barriers.
As a simple guideline, deeper embedment and larger footing diameters are used when bollards are taller, subject to higher vehicle speeds, or located in poor soil. For critical safety installations, consult structural drawings, ACI design guidance, or a licensed engineer rather than relying on rules of thumb.
Calculating concrete for a bollard footing is the same as any other round pier: you compute the volume of a cylinder, convert from cubic inches to cubic feet, and then to cubic yards before adding waste. The calculator above automates this, but many contractors like to verify by hand on a notepad or in the truck.
This concrete bollard footing calculator is intended for general volume estimates and material planning. Crash‑rated vehicle barriers and engineered security systems rely on specific footing geometry, rebar cages, and concrete strengths. Always follow project drawings, manufacturer details, and local code requirements when installing security bollards.
The reference table below shows approximate concrete volumes and bag counts for a few common bollard footing sizes using a 10% waste factor. These are not design recommendations; they are simply examples to help check your calculator results and planning quantities.
| Footing Size (Diameter × Depth) | Volume per Footing (cu ft) | Volume per Footing (cu yd) | 80 lb Bags* | 60 lb Bags* | Use Case |
|---|---|---|---|---|---|
| 12 in × 18 in | ~1.2–1.3 | ~0.05 | 3–4 | 4–5 | Light‑duty decorative |
| 14 in × 24 in | ~2.0–2.2 | ~0.08 | 4–5 | 5–6 | Parking lot posts |
| 16 in × 30 in | ~3.5–3.7 | ~0.13–0.14 | 6–7 | 8–9 | Storefront / sidewalk |
| 18 in × 36 in | ~5.3–5.6 | ~0.20–0.21 | 9–10 | 12–13 | Heavier‑duty perimeter |
*Bag counts are approximate and will vary slightly by brand, mix, and actual bag coverage.