Epoxy Coating Calculator
Estimate epoxy wet film thickness, dry film thickness, practical coverage, gallons, coats, and rounded kit count using solids by volume, surface profile, porosity, transfer loss, and waste.
⚙Project Presets
Pick a coating scenario, then fine tune the film build, area, and waste to match the product data sheet.
📏Film and Coverage Inputs
Epoxy Coating Results
🧪Core Coating Data
📊Reference Tables
Use these tables as quick checks beside the calculated result and the product technical data sheet.
| Epoxy System | Solids Used | Common DFT per Coat | Theoretical Coverage | Typical Role |
|---|---|---|---|---|
| Waterborne epoxy primer | 45 percent | 3 to 5 mils | 144 to 241 sq ft/gal | Concrete sealer coat |
| Solvent epoxy primer | 60 percent | 4 to 6 mils | 160 to 241 sq ft/gal | Penetrating primer |
| 100 percent solids epoxy | 100 percent | 8 to 16 mils | 100 to 201 sq ft/gal | General floor build |
| Flake broadcast base | 95 percent | 12 to 18 mils | 85 to 127 sq ft/gal | Wet bed for flakes |
| Novolac epoxy lining | 100 percent | 16 to 24 mils | 67 to 100 sq ft/gal | Chemical resistance |
| Substrate Condition | Profile Factor | Porosity Factor | Calculation Note |
|---|---|---|---|
| Sealed concrete, CSP 1-2 | 1.03x | 1.00x | Low absorption; film target dominates. |
| Diamond-ground concrete, CSP 2-3 | 1.08x | 1.05x | Common floor preparation allowance. |
| Shot-blasted concrete, CSP 3-4 | 1.14x | 1.10x | Profile valleys increase wet demand. |
| Pitted concrete, CSP 4-5 | 1.22x | 1.18x | Patching and low spots raise usage. |
| Sanded wood or plywood | 1.10x | 1.22x | First coat can soak into open grain. |
| Film Target | 100% Solids WFT | 75% Solids WFT | 45% Solids WFT | Use Case |
|---|---|---|---|---|
| 4 mil DFT | 4.0 mils | 5.3 mils | 8.9 mils | Primer or thin seal |
| 8 mil DFT | 8.0 mils | 10.7 mils | 17.8 mils | Light floor coat |
| 12 mil DFT | 12.0 mils | 16.0 mils | 26.7 mils | Garage build coat |
| 18 mil DFT | 18.0 mils | 24.0 mils | 40.0 mils | Broadcast base |
| 24 mil DFT | 24.0 mils | 32.0 mils | 53.3 mils | Heavy lining |
| Application Method | Transfer Efficiency | Best Film Range | Practical Check |
|---|---|---|---|
| Notched squeegee then backroll | 94 percent | 8 to 25 mils WFT | Most predictable for floor epoxy. |
| Roller only | 88 percent | 4 to 12 mils WFT | Good for primers and thin topcoats. |
| Airless spray | 78 percent | 4 to 16 mils WFT | Overspray and masking loss matter. |
| Brush and detail work | 82 percent | 3 to 10 mils WFT | Edges, coves, penetrations, small areas. |
| Vertical roller application | 84 percent | 4 to 14 mils WFT | Sag risk limits wet film build. |
⚖Coating System Comparison
💡Calculation Tips
When you are planning to use epoxy for a floor projects, you must calculate how much epoxy you need to complete the job. Otherwise, you will run out of epoxy before you can complete the project. The problem with running out of epoxy is that epoxy have a limited pot life.
The pot life is the amount of time you have to apply epoxy before it will harden in an epoxy container. If you run out of epoxy, you cant stop the project to go buy more epoxy. You will have to use the epoxy that has already been applied to the floor to ensure that the epoxy floor is level and seamless.
How Much Epoxy Do You Need for a Floor Project
In most cases, people use the labels on the epoxy cans to calculate how much epoxy they need for there project. However, the label doesnt take into account the texture of the concrete slab that they will be applying the epoxy to. The texture of the concrete, also known as the surface profile of the concrete, will determine how much epoxy the concrete slab will absorb.
If the concrete slab is smooth, it will absorb less epoxy than a slab with a rough texture. This is because a smooth slab will have fewer holes in the concrete than a rough slab, which will have many high points and low points in the concrete. In order to create a seamless epoxy floor, the epoxy must fill all the low points in the concrete.
Therefore, you must consider the surface profile of the concrete when calculating how much epoxy will be needed for the job. Another thing that you need to understand about epoxy is the difference between wet film thickness and dry film thickness. Wet film thickness will measure the thickness of the epoxy while it is in it’s liquid form.
Dry film thickness will measure the thickness of the epoxy when it has cured and the solvents has evaporated. The dry film thickness will always be less then the wet film thickness because the epoxy shrinks during the curing process. The solids by volume of the epoxy will tell you how thick the wet film needs to be applied so that the dry film will be the desired thickness.
The higher the solids by volume, the less amount of epoxy you will need to apply to achieve the desired thickness. The method that you use to apply the epoxy will change the amount of epoxy that you use. One of the best methods is using a notched squeegee.
This tool will allow the contractor to spread the epoxy evenly and will reduce the amount of epoxy that is wasted. Rollers can also be used to apply epoxy but are less efficient than squeegee. Rollers will soak up the epoxy.
Airless sprayers are the fastest way to apply epoxy but will cause overspray. Overspray is the amount of epoxy that gets sprayed into the air instead of being applied to the floor. Therefore, the method that you use to apply epoxy will change the amount of epoxy needed for the floor project.
You can also incorporate a waste and safety allowance for the epoxy that you will purchase. A waste and safety allowance is used for the epoxy that will stick to the mixing bucket or that will be absorbed by the concrete. Ten percent is usually the waste and safety allowance for epoxy but can be as high as twenty percent for very old concrete.
It is better to have extra epoxy than to run out of epoxy during the project. A shortage of epoxy will make the epoxy floor too thin. You will have to buy epoxy in kits for your flooring project.
The amount of epoxy that you calculate for your project may not be the amount that is available in the kits. For example, if you calculate that you will need 7.2 gallons of epoxy, you will have to purchase enough epoxy kits to provide for 7.2 gallons. So you will have to buy 9 gallons of epoxy.
This will ensure that you do not have to stretch the epoxy too thin. If you stretch the epoxy too thin it will create bubbles in the epoxy that will eventually peel off the concrete floor. The pot life of the epoxy begins as soon as you mix the epoxy and the hardener together.
If you mix too much epoxy at one time, it may harden in the mixing bucket before you can pour it on the concrete floor. You will have to work in batches of epoxy so that the epoxy remains in its liquid form. If you manage the life of the epoxy and the volume of the epoxy with precise math, you can create a seamless epoxy floor that will adhere to your concrete floor without bubbling or peeling.
