All you have to do to find an answer to this question is look at the beginning of the story. I'm including a link in case you don't have the text with you.
Basically, the house still looks fine from a distance, but it is falling apart. In addition, it looks kind of spooky.
We can see that it looks spooky because the narrator says it fills him with melancholy just to look at it. And he says that the windows are like vacant eye sockets in a skull.
Then, if you look in the fifth paragraph (that starts "Shaking off from my spirit") you will find descriptions from close up. It talks about how there is a zig zag crack (hardly visible) in the wall. It talks about how the stones seem to be crumbling -- there are lots of details there.