Stacked Stone/Rubble Foundation

[TRAK.Structural]

Anyone have any experience with repair mortars for old stacked stone/rubble foundation walls? I have a situation where a contractor is wanting to keep existing foundations for a home that is having some work done on the wood floor framing. The foundations are stable and mostly in tact so I think this is reasonable but I am considering trying to add some sort of parge coating to more or less provide some extra insurance. The existing stone and mortar will still take all the load, but I'm hoping there is something out there that can help to contain/confine these walls from breaking loose, any ideas?

 

[gte447f]

I would literally do nothing unless there are areas that are loose and crumbling or otherwise need repair.