Example data
Use these example zones to understand typical entries. Replace values with your real measurements.
| Zone | Shape | Length | Width | Diameter | Upturn | Use case |
|---|---|---|---|---|---|---|
| Raised Bed A | Rectangle | 10 | 4 | — | 0.5 | Bed liner under gravel or walkway fabric |
| Hoop House | Rectangle | 20 | 10 | — | 0.75 | Moisture control under greenhouse flooring |
| Round Pad | Circle | — | — | 6 | 0.25 | Small shed base or planter pad |
Numbers shown in feet; switch units if you work in meters.
Formula used
Base area
- Rectangle: Area = Length × Width
- Circle: Area = π × (Diameter ÷ 2)²
- Custom: Area = Measured area input
Upturn allowance
If the sheet turns up edges, extra material is needed:
Upturn Area = Perimeter × Upturn Height
For circles, perimeter is circumference: π × Diameter.
Total required
Required Area = (Base Area + Upturn Area) × (1 + Waste% ÷ 100)
Rolls Needed = ceil(Required Area ÷ (Roll Width × Roll Length))
How to use this calculator
- Pick your units and set a waste percentage.
- Add one or more zones for each garden area.
- Select a shape and enter dimensions or custom area.
- Enter upturn height if the sheet turns up edges.
- Optionally enter roll size and cost per area.
- Press Calculate to see totals and downloads.
For irregular zones, measure area with grid paper, mapping apps, or sectioning into rectangles and triangles, then enter as custom area.