» Mon Oct 17, 2011 6:33 am
Well, the easy answer is anything with INT in it, is interior. Anything with EXT in it, is exterior. A floor would be interior, of course, ceilings too.
Anything that doesn't specify is hit and miss. They can, and are, used for both interiors and exteriors. I would suggest to use the lower grade on anything you're not sure about.