House front wall cracks

Question

I was decorating my hallway and noticed hairline crack going above the front door. Scratched off the front layers and underneath found much wider crack is this something to worry about or just fill it up, paint it and forget about it? Note this front area gets really hot in summers as sun is pointing at that side for the hottest part of the day. Have noticed few hairline cracks also on other windows but nothing on the outside brick wall.

Answer 1

That looks like a poor finishing job. The corners weren't done well either. It most likely is expansion and contraction that gets exacerbated in colder weather. ( you didn't indicate your location) The large crack should be covered with mesh tape, then spackled over and smoothed then painted. The other cracks are normal as said.