What is causing these ceiling cracks?

[bungalow1]

Good evening Everyone,

I moved into my current house 2 years ago and have recently noticed some cracks in the kitchen ceiling. ( I think the previous owner had these touched up as they were not visible when I moved in.) I think these have worsened recently.

I am planning to fill the cracks this week with "Red Devil" from Toolstation as I have read some good reviews.

Before I cover the cracks I wanted to make sure they were nothing more sinister. They run almost entirely around the kitchen ceiling which is part "flat roof" - a very cheap 1980s extension - where the rear wall was knocked through. Are the cracks likely caused by a change in temperate or movement? Or poor construction? I just wanted to rule out structural issues really. Should they have re-appeared after being cosmetically covered 2 years ago?

Any opinions gratefully received.

 

[Doggit]

This isn't an uncommon problem at the ceiling wall junction, and it's possible that the plasterer didn't tape the joint before plastering everything. It could be that they redid the joing every year or two, or as you suspect, just before they put the place up for sale, so it's lasted 2 years. Normally coving would be used to handle this problem.

 

[Tdw1982]

Nothing sinister looking there. A bit of caulk and it's good for another few years.