system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: What causes 'house noises', and when does it become dangerous?
gpt
Homes heat and cool over the course of the day, and the structure of most wood frame houses will creak a bit because the heating and cooling tends to be uneven (it's typically warmer in the upper floors of a house). 

It's only dangerous if the house is actually improperly built and is structurally unsound.