Bonding/ chase moisture problem

[ConorDIY]

Hi there,

I have been struggling with some areas of a wall I previously posted about post a rewire and room replaster. After trying everything to resolve at the surface level I decided to crack out the plaster and found it to be damp underneath.

I believe the house has an intact damp proof course. The bricks at the bottom of the wall have a tolerable level of moisture on my meter. Solid wall construction, ive got this problem across multiple plug sockets on external walls.

I am mapping out where the moisture levels are high and will rake that out. The bonding/sand & cement (unsure) at the bottom of the wall has off the scale resdings for moisture, is hardwall a better alternative or something else for skirting to nail into? The chase seemed to have been filled with bonding also that had off the scale readings too. Ive been trying to get more hands on. What would be your advice for this? Back to brick for where the damp is?
Thank you in advance.
Conor

 

[foxhole]

Your meter is likely for timber and pretty useless in masonry, Your main problem is locating the reason for any damp if indeed you have any.

 

[ConorDIY]

Dont worry, its got a building materials setting meant for masonry which seems to track well (or at least it agrees with my eyes when theres something visibly wrong ).
The pointing on the outside seems fine, no visible gaps. I've cut back any possible bridge-able substrates.
Do you think I should relax and just go about filling the chase with a more suitable material for external walls?