Condensation?

[Just1Cornetto]

Hello, I was hoping for some help identifying a problem. Above my kitchen window (fitted in 2018) there is a cavity. Started noticing occasional drips of water back in February this year. Have considered a leaking pipe (bathroom is directly above) but then thought not otherwise dripping would be constant and there'd sometimes be weeks between any dripping. Eventually, I thought maybe it was a leak in the bath waste where it passes through the wall. I replaced that two weeks ago and no drips. Today they're back. I busted a hole through the plaster to investigate and this is what I see. To me, it looks like a case of bad condensation. We have just had a couple warm days and now temperature has dropped again. Am I wrong? If so, any ideas what it could be? If not, any ideas how I can remedy this? Thank you.

 

[jj4091]

Is you last pic looking up the cavity? If so it does not look like you have a cavity tray fitted above the window so any rain penetrating the outer skin and getting into the cavity will probably come out in the area where you have made the hole

 

[Just1Cornetto]

Thanks for the réply. Yes, that's looking up into the cavity. No tray or weep vents fitted. Just an empty cavity. Block on one side, plasterboard on the other. Outside wall is rendered and I filled any and all cracks around the area a few months back. Do you think it looks like rain coming in or would you say it's interstitial condensation in the cavity?

 

[foxhole]

Is that a copper pipe in the photo ?

 

[Just1Cornetto]

It's not mate. It's a bit of timber for the plasterboard. No pipes in the cavity at all. Just concrete, timber and plasterboard.

 

[Wayners]

Cavity trays missing?
Wall vents to allow air flow?

 

[Just1Cornetto]

Cavity trays missing?
Wall vents to allow air flow?

No tray, no weep vents. Just an empty cavity. My next move is to remove the plasterboard above the window, dry it all out by hand and observe for any more water build up. I'll also wait for the next bit of rain to see if it's ingress. If it stays dry, I'll take it it was indeed condensation and install retrofit 25mm vents above the window. Main thing is to illiminate the possibility it's a leaky pipe in the bathroom above or rain coming in.