Calculation Results
Roll Comparison
| Roll option | Effective coverage | Rolls required | Unused fabric | Fabric cost | Layout |
|---|
Suggested Strip Layout
Complete Result Summary
Formula Used
Rectangle: area = length × width. Circle: area = π × radius². Triangle: area = base × height ÷ 2.
Trapezoid: area = (base one + base two) × height ÷ 2. Net area equals total sections minus excluded areas. Plant openings are deducted only when selected.
Gross fabric includes edge, seam, overlap, and waste allowances. Rolls required equal gross fabric divided by effective roll coverage, rounded upward. Staple totals combine edges, seams, interiors, and safety allowance.
How to Use the Calculator
Add each landscape section and select its shape. Enter dimensions using any supported unit. Add every obstacle that will remain uncovered.
Enter one or more roll sizes and prices. Set overlap, buried-edge, waste, planting, staple, and mulch options. Choose imperial or metric results.
Select calculate to compare roll choices. Review the recommended combination, cost estimate, staples, seams, and unused material. Export or print the completed result.
Example Data
| Input | Example value | Purpose |
|---|---|---|
| Landscape section | 30 ft × 18 ft rectangle | Defines the main bed |
| Obstacle | 6 ft diameter pond | Removes uncovered area |
| Roll option | 4 ft × 250 ft | Compares available fabric |
| Side overlap | 6 in | Allows secure strip seams |
| Waste | 10% | Covers cuts and mistakes |
| Staple spacing | 2 ft edges, 4 ft interior | Estimates fastener quantity |
Frequently Asked Questions
How much overlap should landscape fabric have?
Many installations use several inches of side overlap. Wider overlaps help on slopes, loose soil, or windy locations. Follow the fabric manufacturer’s instructions.
Should plant holes reduce the purchased fabric quantity?
Usually they should not. Openings are cut after full sheets are placed. The calculator deducts them only when requested.
Why does the calculator round rolls upward?
Partial rolls cannot normally be purchased. Rounding upward prevents shortages during installation. Unused fabric remains available for repairs.
How is edge allowance estimated?
The calculator multiplies perimeter by the selected buried-edge width. This represents fabric tucked into border trenches. Irregular edges may need extra material.
How are staples calculated?
Edge staples use perimeter spacing. Seam staples use estimated seam length. Interior staples use a square spacing grid.
Can I compare different roll widths?
Yes. Add several roll options with dimensions and prices. The calculator compares quantities, waste, coverage, and estimated cost.
What fabric type should I choose?
Woven fabric suits drainage and long-term beds. Non-woven fabric offers strong separation. Biodegradable fabric suits temporary weed suppression.
How accurate is the strip layout?
The layout uses an equivalent rectangular footprint. It is an informed planning estimate. Complex curves and narrow sections require field adjustments.
Does the calculator include mulch?
Yes. Enter mulch depth to estimate volume. Results include cubic feet, cubic yards, or cubic metres.
Can mixed measurement units be used?
Yes. Each area, obstacle, roll, overlap, and opening can use supported units. Calculations convert values internally before reporting results.
Should I add more waste for irregular beds?
Yes. Curved borders, many obstacles, and short roll widths increase offcuts. A larger waste percentage provides a safer purchase estimate.