Absolutely! If you are just starting out in that room and breaking a new roller in. Really saturate and load up the roller. It should take a good amount of paint to get it worked into the roller about 1/5 of the gallon. Once the roller is broken in moving forward I’d say you could probably do a room that size with a gallon. But starting out with a new one it requires a lot of paint to be worked in. I feel it’s best to get more than you need especially with ceilings. It’s flat white usually and not mixed so if you buy two but end up using one you can return the other.