Coverage rate is how many square feet one gallon of coating will cover at a given thickness. It is usually listed on the product data sheet as square feet per gallon.
Understanding Coverage Rate
Manufacturers list coverage as square feet per gallon at a set wet film thickness. For example, a 100 percent solids epoxy at 10 mils covers about 160 square feet per gallon. A thicker coat covers less area, and a thinner coat covers more. The number on the data sheet is a perfect-world figure.
What Affects Real-World Coverage
Rough or porous concrete soaks up more material and lowers your coverage. Shot blasted floors take more than smooth ground floors. Waste in the bucket, roller loss, uneven slabs, and heavy back rolling all use material too. Most installers add 10 to 15 percent to their estimate to cover this.
Coverage Rate vs. Mil Thickness
Coverage rate and mil thickness are two sides of the same math. As the film gets thicker, coverage per gallon goes down. If you spread a gallon thinner to stretch it, you may fall below the required thickness and hurt wear life and appearance.
Practical Tips for Estimating Coverage
Measure the full area and subtract nothing until you have checked the slab profile. Check the data sheet for each coat, including primer, body coat, and topcoat. Do a test patch if the concrete is very porous. Round up to full kits, and keep a small reserve for touch-ups.
Also Called
Spread rate, Square feet per gallon
