First time posting, squee! Anyway, not sure if this has been brought to your attention yet. And I haven't tested it with a farm. But! The details are as follows.

Apparently if you build a building over a square that is being torn down before it is finished being town down. Like an exhausted Farm or well. Then the square glitches out till the square is Drained of the recources that would have been build there. Then you can rebuild on said square again.

Caused this to happen twice now in the exact same spot. Deep well glitched out twice. Not consecutively because I had a well placed in between.

Also not certain if it takes the recources to build it but yeah!