When you dream about your house, it often represents your self and the different rooms symbolize different aspects of your character. The doors to the rooms reflect how you express and access these different parts of yourself. Discovering a previously unnoticed door in a dream usually indicates that you have the opportunity to step into an exciting new possibility in your waking life.
The room the door opens into is often familiar because it represents a talent that you were passionate about in the past but had to step away from for a while. For some reason you had to close the door on this opportunity and forget about it but now you have the chance to step back into the potential that it holds.
This dream often occurs when some space opens up in your waking life and you have the time to return to your old passion. The size of the room reflects the magnitude of the opportunity and the room often seems to stretch off into the distance, or leads on to a whole series of other rooms.
This indicates that exploring the initial possibility will lead onto a number of other exciting opportunities and give you the chance to expand well beyond where you are just now. The contents of the room reflect the nature of the talent or passion that you closed the door on. They may be a bit dusty or rusty but they are still intact and waiting for you to put them back into regular use.
Even though you think you know your achievements and your limitations, you have unknown talents you have yet to discover. The chance to explore this talent often comes in the form of an unexpected opportunity.
Like any room it can take some time to realize the best way to use it as you furnish your ambition. You need to be open to opportunity and not close the door on any chances that you create. As you start to explore one talent, you often start to become aware of other possibilities for using your unique abilities.
One of the main ways we learn is by making analogies, and one of the first analogies we make is using our house to symbolize our own self. A house has an inside and an outside and we all have an inner life and an outer life.
Space is usually at a premium in most of our houses and the number of rooms it contains most often reflects its value. In the same way that houses can be extended to provide more room, the more that we extend our abilities, the more often we encounter valuable character building opportunities.