Do you need battlefield bad company 2 installed to play Battlefield Vietnam?

I own Battlefield Bad Company 2 on Steam but don't have it installed. I want to buy the Battlefield Vietnam expansion, would I have to have Battlefield Bad Company 2 installed for Vietnam to work?|||Not installed, You need the disk as it is a DLC, You simply start the game normally and scroll through the menu to 'battlefield bad company 2 vietnam' its next to multiplayer.|||Yes, it's an expansions for battlefield bad company 2 xD|||Indeed|||Yes, this is an add-on, not a standalone game.|||Yes, you would.