I really like the heavy grain.

At first, I debated about the composition. Is the subject well placed? I'm the first to break the rule of thirds, but find that similar shots like this command/demand the rule.

But after looking at it on the screen and playing it in my mind, the picture really is much more than the structure. The placement of the opening of the sky is an integral part of the picture. What looks like a small stairwell gives a bit of interest, some balance, and quite a bit of mood to that area of the frame.

It's one of those pictures where a critique really takes some time- you have to ask yourself what is it that appeals to you so much as it's many subtle qualities. What you'd normally suggest needs to be done to make it better could easily destroy the mood.

Great job.