Continuous crack - should I be worried?

[ehe17]

Renovating a house from the 1930s, and have just shoveled out the subfloor's sawdust. The house has some cracks in the slab that forms the basement ceiling, which is to be expected in a house with over 10 cm level difference due to settling.

However, I found this crack that seems to go through the entire slab. Should I be worried, or is this also within the normal range?

 

[cpalm]

Are the walls in the basement newly cast?

 

[ehe17]

Are the basement walls newly cast?

Yes, but the crack is old.

 

[cpalm]

Yes, but the crack has been there for a long time.

Well, I was thinking more about whether the cause of the crack might have been an issue with the walls that has now been fixed?

 

[ehe17]

Well, I was thinking more about whether the cause of the crack could have been some problem with the walls that has now been fixed?

Oh, now I understand. Yes, it's very possible. The walls bulged inward so much that we decided to replace them. This was one of the better corners of the house in terms of walls, but also the side that had sunk the most.

 

[M85]

The house is 90 years old so it's probably not urgent, but what are the other settlements?

 

[ehe17]

The house is 90 years old, so it might not be urgent, but what are the other settlements?

Clay ground has sunk 10 cm in one corner.

 

[M85]

Is the entire house on clay or only parts of it?

 

[ehe17]

Old lake bed, so moraine and clay. The neighbor has bedrock under their basement but has no idea.