Inputs
Formula Used
- Rectangle perimeter: P = 2 × (L + W)
- Circle perimeter: P = 2 × π × R (or π × D)
- Custom perimeter: P = Σ(segment lengths)
- Gate openings: G = gate_count × gate_width
- Net run: N = max(0, P − G)
- Adjusted run: A = N × (1 + waste_pct / 100)
- Panels / rolls: panels = ceil(A / panel_length)
- Post intervals: intervals = ceil(A / spacing)
- Total posts: corners + (2 × gates) + max(0, intervals − corners − 2 × gates)
- Concrete volume: V = posts × π × (d/2)² × depth
How to Use This Calculator
- Select units and a layout type that matches the site.
- Enter geometry: rectangle, circle, or custom segments.
- Add gates to subtract openings from barrier material length.
- Set waste/overlap and spacing based on your method.
- Enter panel length and optional material selections.
- Fill in cost assumptions to estimate a total budget.
- Submit to view results, then export CSV or PDF.
Example Data Table
| Scenario | Layout | Inputs | Key Outputs |
|---|---|---|---|
| Temporary boundary | Rectangle | 30×20 m, 1 gate × 4 m, 5% waste, spacing 2.5 m, panel 3.5 m | Perimeter 100 m, adjusted run 100.80 m, panels 29, posts ~40 |
| Round laydown area | Circle | Radius 10 m, 0 gates, 7% waste, spacing 2.4 m, panel 3.0 m | Perimeter 62.83 m, adjusted run 67.23 m, panels 23, posts ~28 |
| Irregular site edge | Custom | Segments: 12,18,10,15 m; 2 gates × 3 m; 8% waste | Perimeter 55 m, adjusted run 52.92 m, panels 16, posts ~22 |
Perimeter Definition and Site Control
A perimeter barrier plan starts with a clear boundary line that matches the work limits, storage zones, and public interfaces. This calculator lets you model rectangles, circles, or irregular edges so the measured run reflects real site geometry. Use the same unit system as your survey or setting-out notes, and confirm that the boundary closes without gaps. When the perimeter is defined correctly, subsequent counts for panels, posts, and accessories become defensible for procurement and approvals.
Gate Opening Allowances
Gates reduce barrier material length but add framing, bracing, and hardware. Enter the number of gates and the clear opening width to subtract total openings from the perimeter. The calculator reports both the net run and the adjusted run after waste is applied, helping you avoid double counting. If vehicle traffic is heavy, consider wider gates or separate pedestrian access points to keep the barrier continuous and safer.
Spacing Rules and Post Counts
Post spacing affects stability and the final post count. The model uses an interval approach based on the adjusted run, then adds corner posts and gate posts where applicable. Tighter spacing increases posts and labor but improves stiffness in wind-prone areas. For temporary systems, match spacing to supplier recommendations and ground conditions. Always review corners, slopes, and tie-ins where extra posts are commonly needed.
Material Takeoff and Waste Factors
Panel or roll quantity is calculated by dividing the adjusted run by the selected piece length and rounding up. Waste and overlap cover returns, overlaps at joins, and minor alignment losses. Typical allowances range from 3–10%, but complex layouts may require more. Optional top rail length and mesh area support fencing packages that include continuous rails or fabric. Concrete volume estimates use a cylindrical footing model per post when diameter and depth are provided.
Cost Drivers and Scenario Checks
Costs are split into run-length materials, panels/rolls, posts, gates, and labor per length. This structure supports quick scenario comparisons: adjust spacing, waste, or gate counts and observe the impact on totals. Validate the output against supplier bundles and minimum order quantities, then apply local rounding rules. A practical check is to compare adjusted run versus base perimeter and confirm that openings and waste move the results in the expected direction before exporting reports.
FAQs
1) Which layout should I choose?
Use rectangle for simple sites, circle for round pads, and custom segments for irregular boundaries. Choose the option that best matches your measured edge lengths to keep the takeoff realistic.
2) Why does the adjusted run exceed the net run?
Adjusted run includes your waste/overlap percentage. It accounts for overlaps at joints, small alignment losses, and practical rounding during installation, so you avoid shortfalls during procurement.
3) How are posts estimated?
The calculator estimates post intervals using the adjusted run and spacing, then adds corner and gate posts. Final layouts may require extra posts at corners, ends, slopes, and tie-ins.
4) Can I model multiple gates with different widths?
This version uses one gate width applied to all gates. For mixed widths, run separate scenarios or use custom segments and subtract openings manually using the net run logic.
5) What footing values should I enter?
Enter footing diameter and depth only if you need a concrete estimate for posts. Set either value to zero to ignore concrete volume and keep the output focused on barrier quantities.
6) Do export files include my cost inputs?
Yes. The CSV and PDF exports include the key metrics and the cost breakdown totals based on your entered rates, helping you share assumptions and results with stakeholders.