Do you know whether the house was made by mods or weird third party custom content? (I know that it's against the rules to discuss them, but I'm going to bend them a little for now since it can clearly be the culprit)
If this is possible to have occured, I'd say you should delete the house and everything that came with it and see if it helped. Otherwise, make a clean re-install; there are tips and instructions in the sticky threads in Technical Help, but let's first see if somebody else can come up with something.
The other thing I can imagine is that it may have glitched up during installation, where I'd also suggest you should see if it helps to get rid of it.
Then again, the problem may be unrelated, but start with the above suggestions.