new to me house, we are painting and I took off the vent and discovered that it was just hanging out there, with a ton of leaves in it. This is the second floor. we've got -20 wind chill so I'm not going to poke around outside right now but I'm open to any advice on figuring out what is going on there... All of the vents look like this, I can clean them out but is it proper to bend the sheet metal down As much as possible and put mastic tape around? I've gathered this from reading some other posts here but I'm not sure what else needs done. Red arrow shows the gap between sheetrock and floor... Well actually behind the floor. can this be filled somehow with something flexible? It's pretty big for caulking... But lots of cold air coming in along the baseboards everywhere. last photo shows where I've bent the sheet metal edges down and cleaned up as much as possible. You can see how black the carpet is up against the vent.