Potential Damp patch in Bedroom?

[Jimbo2001]

Hi there,

First time poster needing some advice if possible.

Recently discovered a foisty smell in my bedroom. Looked behind my bedside unit and could see a patch of what looks like damp. The back of the unit had green mould dusting all over but the actual walls only shows what looks like a water mark.

It's on the lower corner of my room, the left hand or the picture faces east and the other side faces south. I wasn't sure if it was a case of poor circulation or maybe water getting in through a down pipe fixing outside. I used a 2 prong moisture reader, albeit a very basic one, and for readings of between 14 and 16.4. I understand this to be relatively normal, but again Im not confident that the equipment used is any good.

I've attached a picture and welcome any feedback on what it looks likely to be and if there's a way I can treat it.

TIA

IMG-20210225-WA0013.jpeg (158.31 KiB) Viewed 1286 times

[Ken010]

Can I suggest you re-test the affected wall? this time do NOT push the probes into the plaster, instead place the probes on the surface and gently drag he probes over the wall. Because if the surface is "damp" then a reading may be obtained, that would then in turn imply that the dampness is condensation.

Next try the probes in other rooms, obtain a [sort of a ] Datum by which you can judge the moisture content in the affected room.

Also if you can have a look outside in and above the affected area, see if you can see any cracks in the roughcast or cracks in the brickwork and finally, has the property had cavity wall insulation retro-fitted?

Ken.