This may sound very basic, but how do you identify a load- bearing wall? I have a 3-4 ft wall which separates 2 rooms on one side that I would like to remove (lathe and plaster) to open it up as one big room but I don't know if it can be done. There is about a 6 foot wall across the room from it that will stay in place. Would this be sufficient to bear the load? If not, what has to be done to remove this wall safely? Thanks.