Epoxy Floor Calculator
Estimating epoxy for a floor is mostly about area and coat count. This guide gives you coverage per gallon at every thickness, room-size reference tables, and a breakdown for garage, basement, and commercial floors — so you buy exactly what you need.
Use the free calculator to get a precise epoxy estimate for your floor project.
Calculate Epoxy Amount →Coverage Per Gallon by Coat Thickness
Standard epoxy floor products cover 200 sq ft per gallon at 1/16 inch. Thicker coats reduce coverage proportionally. Use the table below to estimate how many gallons you need per coat.
| Coat Thickness | Coverage per Gallon | Gallons per 100 sq ft | Gallons per 500 sq ft |
|---|---|---|---|
| 1/32 in (0.8mm) | ~400 sq ft | 0.25 gal | 1.25 gal |
| 1/16 in (1.6mm) | ~200 sq ft | 0.5 gal | 2.5 gal |
| 3/32 in (2.4mm) | ~135 sq ft | 0.75 gal | 3.7 gal |
| 1/8 in (3mm) | ~100 sq ft | 1.0 gal | 5.0 gal |
| 3/16 in (4.8mm) | ~65 sq ft | 1.5 gal | 7.5 gal |
| 1/4 in (6mm) | ~50 sq ft | 2.0 gal | 10.0 gal |
Coverage assumes smooth concrete. Rough or porous concrete can reduce coverage by 15–25%.
Total Gallons by Room Size and Coat System
Most floors use a 2-coat system (basecoat + topcoat). Here's the total product needed including both coats and a 10% waste buffer.
| Room Size (sq ft) | 1-Coat System | 2-Coat System | 3-Coat System |
|---|---|---|---|
| 100 sq ft | 0.5 gal | 1.1 gal | 1.6 gal |
| 200 sq ft | 1.1 gal | 2.2 gal | 3.3 gal |
| 400 sq ft (2-car garage) | 2.2 gal | 4.4 gal | 6.6 gal |
| 500 sq ft | 2.8 gal | 5.5 gal | 8.3 gal |
| 800 sq ft | 4.4 gal | 8.8 gal | 13.2 gal |
| 1,000 sq ft | 5.5 gal | 11.0 gal | 16.5 gal |
| 2,000 sq ft | 11.0 gal | 22.0 gal | 33.0 gal |
Based on 1/16 inch per coat. Adjust for thicker pours using the coverage table above.
Standard Floor Coat Systems by Application
| Application | Coat System | Total Thickness | Notes |
|---|---|---|---|
| Residential garage | Basecoat + topcoat | 1/8 in | Add color chips between coats |
| Basement floor | Primer + basecoat + clear | 3/16 in | Moisture barrier primer critical |
| Commercial kitchen | Primer + 2× base + 2× clear | 1/4–3/8 in | Anti-slip aggregate in topcoat |
| Warehouse / industrial | Basecoat + 2× high-build | 3/8–1/2 in | Self-leveling mortar system |
| Decorative metallic | Primer + 2× metallic + clear | 3/16 in | No broadcast; smooth finish |
⚠ Moisture Warning: Tape a 2-ft plastic sheet to the slab and seal the edges. Wait 24 hours — if condensation forms under the plastic, the slab has too much moisture for standard epoxy. Use a moisture-tolerant primer or wait until the slab dries.
Coat Thickness Guide
Choosing the Right Thickness
- 1/16 in (thin topcoat): Best for a clear sealer or final protective coat over color. Not suitable as a standalone floor coat.
- 1/8 in (standard basecoat): The workhorse thickness for residential and light commercial floors. Good build, hides minor surface imperfections.
- 3/16 – 1/4 in (heavy coat): For high-traffic areas, uneven concrete, or embedded aggregate floors. Requires self-leveling epoxy.
- 3/8+ in (mortar system): Used in commercial kitchens and industrial floors. Requires a trowel-applied mortar basecoat and separate sealer.
Calculating Your Floor: Step-by-Step
- Measure the area — length × width in feet for square/rectangular rooms. For L-shaped or irregular floors, divide into rectangles and add the areas.
- Choose your coat system — how many coats and what thickness each coat will be.
- Multiply: (sq ft ÷ coverage per gallon) × number of coats = gallons needed.
- Add 10% for waste — mixing losses, uneven spreading, touch-ups.
- Add 15–25% for porous concrete — bare, unsealed concrete absorbs more product.
Example: 400 sq ft garage, 2 coats at 1/8 inch each:
(400 ÷ 100) × 2 = 8 gallons × 1.10 = 8.8 gallons
Frequently Asked Questions
How much epoxy do I need per square foot of floor?
At 1/16 inch (typical floor coat), one gallon covers approximately 200 sq ft. At 1/8 inch, one gallon covers about 100 sq ft. Most floor projects use 2 coats: a basecoat at 1/8 inch and a topcoat at 1/16 inch, totaling about 3 gallons per 100 sq ft.
How many coats of epoxy does a floor need?
For a durable floor finish, plan on 2–3 coats: a primer or basecoat (1/8 inch), a broadcast color coat, and a clear topcoat (1/16 inch). Bare concrete may need an additional penetrating primer. High-traffic commercial floors often add a 4th UV-resistant topcoat.
Do I need to prep concrete before applying epoxy floor coating?
Yes — concrete prep is critical. Acid etch or mechanically grind the surface to open the pores, repair cracks, and degrease thoroughly. Moisture testing is also essential — epoxy will peel from a damp slab. Poor prep is the #1 reason epoxy floor coatings fail.