Calculator
Example data
| Use case | Shape | Size | Thickness | Coats | Waste | Estimated volume |
|---|---|---|---|---|---|---|
| Garden workbench top seal | Rectangle | 120 cm × 60 cm | 2 mm | 2 | 10% | ~0.53 L |
| Round planter tray pour | Circle | 50 cm diameter | 4 mm | 1 | 12% | ~0.88 L |
| Decor ring insert | Ring | 60 cm outer, 40 cm inner | 5 mm | 1 | 15% | ~0.97 L |
Formula used
- Rectangle area A = L × W
- Circle area A = π × (D ÷ 2)²
- Ring area A = π × (Rₒ² − Rᵢ²)
- Volume V = A × t × coats × (1 + waste%)
- Liters L = V(m³) × 1000
- Component split A_L = L × a/(a+b), B_L = L × b/(a+b)
- Weight kg = L × density(kg/L)
How to use this calculator
- Pick your shape and choose measurement units.
- Enter dimensions or a custom area value.
- Set thickness, coats, and a waste allowance.
- Enter the mix ratio and optional cost details.
- Press Calculate to see results above the form.
- Use CSV or PDF buttons to save your results.
Surface preparation for outdoor builds
Epoxy performance in garden projects starts with the substrate. Clean, dry, and lightly abraded wood or concrete improves wetting and reduces pinholes. Remove oils, dust, and loose fibers, then seal porous surfaces when needed. A sealed base lowers uptake and keeps calculated volumes closer to the poured volume. Protect soil from drips during work.
Managing pour thickness and heat
Thickness controls both coverage and cure behavior. Deep pours generate heat and can crack or yellow in sun-exposed locations. Use the calculator to split a large depth into multiple coats, letting each layer cool and gel before the next pour. For edging and corners, add a small waste allowance because resin tends to pool. Shade the piece to slow cure.
Allowance for waste and absorption
Wasted material comes from mixing cups, rollers, and level corrections. Rough textures and end grain can also absorb resin. A 5–15% allowance is common for smooth sealed surfaces, while unsealed timber or textured concrete may require more. Track actual usage per job and refine the allowance for future batches. Weigh containers to quantify losses.
Mixing ratios and batch planning
Most systems use a fixed A:B ratio by volume. The split shown helps you measure components accurately and avoid soft spots from off-ratio mixes. For short pot-life products, plan smaller batches that match working time, especially in warm weather. Always mix thoroughly, scraping sides and bottom. Mark cups for repeatable measuring and reduce mistakes under time pressure.
Interpreting liters, kits, and cost
Total liters represent mixed resin needed for the selected area, thickness, coats, and waste. Kit counts round up so you can order sufficient material. If you enter a unit price, the cost estimate supports budgeting for tabletops, planter liners, or decorative inlays. Confirm coverage guidance on your product label. Order extra for touch-ups later.
FAQs
1) What waste percentage should I start with?
Use 10% for smooth, sealed surfaces. Increase to 15–25% for rough textures, deep edges, or first-time pours. Reduce only after tracking real usage across several similar projects.
2) How do I calculate for an irregular garden feature?
Select Custom area and enter the measured surface area. For complex layouts, break the surface into simple shapes, sum their areas, then apply the same thickness and coats.
3) Why does the calculator show component A and B liters?
Many epoxies require a fixed mixing ratio. The split tells you how much of each component to measure so the combined mixed volume matches the total liters you need.
4) Does density change the required epoxy volume?
No. Volume is set by area and thickness. Density is used only to estimate weight for handling, shipping, and planning how heavy the cured layer may be.
5) How should I choose thickness for outdoor garden items?
Use thin coats for sealing and UV topcoats, and build depth with multiple pours. Thinner layers reduce heat buildup and help control bubbles on warm days.
6) Can I rely on the cost estimate for purchasing?
Treat it as a planning figure. Prices vary by brand, kit size, and additives. Confirm your supplier’s price per liter and order an extra margin for touch-ups.