Single-story house with basement

[Emppsan]

When we were going to change the floor in one of the rooms on the entrance level in our recently purchased house (built sometime in the '60s or '70s), we noticed that the wooden beams are directly on the concrete, and a terrible odor was coming from one of the corners (smells somewhat sharp like old ingrained cat pee).
Should we replace all the sills, or is it enough to remove the material that smells?
The smell remains on the marked area, see picture.
How can we replace it most easily?

 

[Dan_Johansson]

Looks like someone has already replaced the bottom part of the standing studs?

 

[Emppsan]

Looks like someone has already replaced the lower part of the standing studs?

Yes, my partner replaced just that part, but the question is whether everything needs to be replaced or just the material that smells? And how do you deal with the stud that is at the bottom? Is it enough to "patch and repair" or do you have to remove everything?

 

[egge80]

Must be difficult to determine which centimeters smell, well, replace everything and put under sill sealer or preferably metal studs.

 

[Emppsan]

Must be difficult to determine which centimeters smell, well, replace everything and put it under sill paper or preferably metal studs

thanks for the reply!