The "1604 Rule" for Epoxy Coverage
Contractors installing professional garage floors rely on the 1604 Rule to accurately quote material costs. The math is simple but absolute: 1 gallon of 100% solids epoxy will cover exactly 1,604 square feet at a thickness of 1 mil.
However, no one applies a floor at 1 mil (which is 1/1000th of an inch). A typical commercial base coat is applied between 10 and 15 mils. If you apply a 10 mil base coat, you simply divide 1,604 by 10, meaning your actual yield is roughly 160 square feet per gallon.
How to Calculate Epoxy Needs
- Step 1: Calculate Square Footage. Measure the length and width of the concrete slab and multiply them. A standard two-car garage is usually 20x20 (400 sq ft).
- Step 2: Determine Mil Thickness. Select how thick you want your base layer. A thicker layer (12-15 mils) hides floor imperfections better and creates a stronger bond.
- Step 3: Run the Equation. The formula is: (Square Footage × Mils) ÷ 1604 = Gallons needed.
Understanding Flake Broadcast Rates
Decorative vinyl color flakes (or chips) are broadcast into the wet epoxy base coat to provide texture, slip resistance, and a granite-like appearance. Your coverage rate dictates the final look:
- Full Broadcast (1 lb per 10 sq ft): The industry standard for high-end professional garage floors. Flakes are applied heavily until rejection (until no more will stick). This completely hides the underlying epoxy color and provides maximum durability.
- Medium Broadcast (1 lb per 100 sq ft): Leaves the base coat color highly visible while distributing a noticeable speckle of color throughout the floor.
- Light / Sparse (1 lb per 250 sq ft): A very light dusting. Usually chosen when the base epoxy color is the main design feature.
Pro Tip: Always order an extra 10% of flakes for a full broadcast job. Sweeping up and reclaiming "rejected" flakes during the installation process is messy and time-consuming. It is always cheaper in labor to have too much flake than to run out halfway through a pour.
