Higher thinking, the spiritual awareness within, higher self, the mind, thoughts, history, past issues, and family history. One of the places within where you put things that you do not know what to do with. Parts of houses or buildings often represents a part of yourself. The attic symbolizes your higher subconscious mind self. It is the apex of your higher self. The condition of the attic determines what is happening within your subconscious self. Is the attic full, cluttered, empty, organized, or messy? If you compare it with your life, you can see if you are feeling fulfilled, overwhelmed, or stuck in the past etc. Either way this is a dream about spiritual development and possibly about cleaning up your physical life, so that you will have less mental clutter that blocks you from moving forward spiritually. Individual symbols in the attic may play an important role symbolically also.
See Home, Organize, Hoarding, Garage, Blocked, Letting Go.