The dark background, the shadows and the eerie light on the building express a sense of foreboding. The "no trespassing" sign heightens this sense by admonishing us to stay away.
This image gives me a creepy feeling. It might even make me obey the sign.........maybe!!
The dark foreground gives this a sense of isolation, and the lit up sign and window make me feel as if I have just happened upon a treasure to explore, albeit forbidden. Did you peek inside to see what was in there??
This is a wonderfully expressive wreck of a building -- you make it so by refining your exposure and creating a mood of abandonment. Pondosa offered us both wonderful subject matter. The place was falling down all around us. My own favorite memory of Pondosa was a crumbling barn, shot very much in the same spirit as your own image:http://www.pbase.com/pnd1/image/103638309