What is epoxy flooringin construction?

Divide the floor area by the manufacturer's coverage rate at the specified film build, then add waste for porous or rough slabs. A thin roll-on coat might cover 250 to 300 sf per gallon, while a self-leveling slurry at 1/8 in covers far less. At 1/8 in, one gallon is 231 cubic inches, so 231 divided by 0.125 in divided by 144 sq in per sf is about 12.8 sf per gallon. Always price coverage per coat at the spec's mil thickness, not a single blanket rate.

Keep it separate. Shot blasting, diamond grinding, crack chasing, and patching are priced per square foot of floor and often carry as much labor and schedule risk as the coating itself. Bury prep inside the coating unit price and you lose the ability to defend the number when the slab condition is worse than assumed, which is common on existing slabs.

Yes. A typical commercial system is primer plus body coat plus topcoat, three applications, each with its own coverage rate and cure time before the next. The total applied area is floor sf times the number of coats, so a 6,000 sf floor with three coats is 18,000 sf of application. Pricing only one or two coats is a common underbid.