Can anyone please explain what is causing this wet damp patch on the floor board here? The underside and sides are completely dry as shown so can't be moisture from bottom at joist level and there are no radiator pipes running, only from under second floorboard. My initial guess is condensation. Room has been newly plastered and windows are left open to dry the plaster during the day and this patch dries up but re appears overnight when windows are closed.
There is no such thing as co-incidence. It's right under the bag. I'd guess the socket in the bag is attracting more condensation as the temperature falls overnight and it's dripping onto the floorboard. Screw your faceplate back on and see if it happens again.
Hmm that makes complete sense. The faceplate is metal and metal is colder so attracts condensation. But then there does not seem to be any moisture on the socket or plastic bag. Anyway will remove bag and screw in faceplate to see if it happens again tonight. Cheers!
Once the air and the socket warms up again the next morning any moisture on the bag will rapidly dry as the temperatures equalize and the warmer air can hold the moisture again. The timber takes longer to release the moisture back into the air because the moisture has been absorbed into the material.
Yeah makes sense now...might even just put a small bucket or something under the wrapped socket to catch the water to confirm all this haha. Painting the room soon so need the sockets wrapped. But then all the other sockets around room are wrapped too and it's dry on floorboards. I guess it's because this is a solid exterior wall so it's colder and hence attracting more moisture.