Cold water copper pipe, insulate or not?

[mderoy]

I’m going to be redoing my bathroom and I noticed that the copper pipe carrying the cold water (in this season) seems very cold and almost misty to touch like it’s sweating. Wondering if this moisture/sweat can potentially start to drip etc. I’m planning to run the copper pipework inside stud walls and have a concealed mixer valve so don’t want any sweat water somehow creating puddles or wet spots. Is it recommended to run cold pipes and hot pipes in the all through those grey foam looking insulation sleeves or is that an overkill?

 

[denso13]

It's condensation and yes, insulation will help.

 

[ChrisJP]

It's not "sweating" - unless there's a leak somewhere.
Normally it's just water vapour in the air condensing out on the cold walls of the copper pipe - kept cold by the fresh water feed coming in as you draw off cold water for household needs. Always worse in the winter when the mains cold water feed is particularly cold.
Insulation will keep the pipe a bit warmer but only as long as there's no fresh cold water flowing through it. It's worth putting on, but it's main role will be to help prevent damp air continually contacting the cold water pipe

 

[endecotp]

I’m planning to run the copper pipework inside stud walls

The humidity inside the wall will be lower than in the bathroom - at least it should be! - so the danger of condensation onto the cold pipe is lower.

Insulating the pipe would still be good practice.