Project guide
Epoxy floors & resin casting: pick the right calculation
“How much epoxy do I need?” has two very different answers. A garage floor coating is a thin film measured by coverage per coat; a river table or resin pour is a solid volume measured by thickness. Using the wrong method can be off by a factor of ten.
Which calculator to use when
What the project involves
Epoxy floor coatings are applied in thin coats, typically a fraction of a millimetre each. Manufacturers state coverage per litre or per kit at a given film thickness, so the quantity depends on floor area, number of coats, and that coverage figure. Porous or rough concrete absorbs more of the first coat, which is why primers and a waste allowance matter.
Casting and table-top resin is different: you fill a volume. One square metre poured one millimetre deep is one litre, so thickness drives everything, and deep pours may need several layers or a dedicated deep-pour resin. Two-part systems must be mixed at the stated A:B ratio, by volume or by weight as the product specifies, so the calculator splits the total into each part before rounding to kits.
Order of work
- Decide which job you have: a thin protective floor coating, or a solid pour, coating, or casting with a set thickness.
- Measure the area with the Square Footage calculator, splitting irregular floors or table shapes into rectangles.
- For floors, use the Epoxy Floor Coating calculator with the coverage per coat from the product data sheet and the coats you plan.
- For pours and table tops, use the Epoxy Resin calculator with the final thickness and the mix ratio printed on the kit.
- Round up to whole kits and buy matched A and B parts from one batch; never split a kit at a ratio other than the stated one.
Common mistakes
- Using a floor-coating coverage figure for a resin pour, or a pour thickness for a floor coating.
- Ignoring concrete porosity: a bare, porous slab can soak up much of the first coat.
- Mixing A and B by eye, or by volume when the product specifies weight.
- Pouring deeper than the resin is rated for in one layer, which can cause heat build-up and cracking.
- Forgetting resin lost in mixing containers, edges, and seal coats when the waste allowance is set to zero.
Common questions
FAQ
Which epoxy calculator should I use for a garage floor?
Use Epoxy Floor Coating. Garage floor systems are thin coats sold by coverage per kit, and the coating calculator works from area, coats, and that coverage rate.
How much resin do I need for a river table?
Multiply the area of the gap by the pour depth: 1 m² at 1 mm deep is 1 litre. The Epoxy Resin calculator does this, adds waste, splits the total into parts A and B, and rounds up to whole kits.
Is the A:B mix ratio by volume or by weight?
It depends on the product, and the two figures are often different. Use the ratio and method printed on your kit; the calculator splits the total by whatever ratio you enter.
Can I pour a thick table top in one go?
Only if the resin is rated for that depth. Many coating resins are limited to thin layers, while deep-pour resins allow thicker single pours. Check the maximum pour depth on the data sheet and plan layers accordingly.