Work out exactly how much epoxy you need — volume, mix ratio, part A/B amounts, and cost.
Covers epoxy left in cups, on stir sticks, absorbed by porous wood, and small spills. 5–10% is typical.
| Net volume (no waste) | — |
| Waste factor | — |
| Total mixed epoxy | — |
| Part A weight / Part B weight | — |
| Estimated cost | — |
For a rectangular pour, multiply length × width × depth. For a round pour, multiply π × (diameter ÷ 2)² × depth. That gives the volume — convert it to liters or gallons, then add a waste factor of about 5–10% to get the amount you should mix.
Epoxy has very low shrinkage compared with polyester or vinyl ester resins — typically under 2% as it cures. Deep pours can generate exothermic heat that causes small voids or dips, which is why a small waste factor is still recommended.
Extra epoxy added on top of the calculated volume to account for material left in the mixing cup, stuck to stir sticks, absorbed into porous surfaces like wood, and small spills. 5–10% is typical; use more for very small or very porous projects.
One gallon of mixed epoxy typically covers about 12 square feet at 1/8" (3 mm) thickness. At 1/16" it covers roughly 24 sq ft, and a thin flood coat at 1/32" can cover around 48 sq ft per gallon.