[lupo]

I would think a gallon It depends on how it would cover. If it's a high solids paint a gallon would do well. They do not list their solid content on their data sheet , they did say that 2/3 coats will cover. It's got an 8 to 1 mix ratio and a slight amount of reducer will bring you close to five quarts which should be enough. You could order another quart to be on the safe side You might want to consider reducing the last coat for better flow out. Paint the floor first so you get the hang of it .I'm sure you'll do a good job.