I am finishing my basement and have just one room left that I need to run a heating duct to. My main heating duct runs parallel to the one bearing wall that goes down the middle of my basement. The room I need to heat is on the other side of the bearing wall. I planned to put a new duct takeoff on top of the main duct and run it over the bearing wall and into the room I need to heat. I noticed recently that there are pieces of wood between every floor joist above the bearing wall that completely block access to the room. The only openings are where there are other ducts servicing the upper floor. Does anyone know the purpose of these plates of wood and if it is safe to remove one? Here is a picture of the wood I am talking about:
