[Castiel considers his question while working on a bite of his sandwich, only responding once he's swallowed. He's picked up some manners, thankfully.]

He took his lighter with him, so I suspect that played a factor.

[Tricking the building into thinking there was a fire would trigger water spraying out, if he thought about it logically.]

We found a key that we think it was bound to and we burned it, but... it isn't enough. We'll need to do more research tomorrow.