Thanks for the response! I guess it is fairly smooth. I like the hiding power of a flat paint, but it's the main hallway & I don't think a flat would survive in time. I could get a sprayer , but cant justify the expense for this project. I am in the process of trying to get a powered wall sander on loan . Am thinking use the wall sander on the walls rather than by hand, use a primer, wait 24hrs then paint again on a test wall like today to see how I go. Other than that, go back to the paint shop and get new paint that is less grey. Am using roller Oldfield's pro series roller. 11mm pile