Help, damp and cracks around window

[Marvors]

Hi
So in my sons room damp seems to have seeped in and around the entire window frame (pictures show from left corner of the window all the way round to the right corner). I have had two window guys out so far, the first put a tube and a half of silicone above the window on the outside of the room... issue still exists, and the second just said the window was fine, didn't know where the moisture is coming from.
Ibahve also attached some images of the window from the outside.

Any ideas?

 

[Notch7]

You have quite a lot of brickwork above the window and the window itself has a concrete lintel rather than a catnic type lintel

My guess would be that rain is penetrating the brickwork, running down the cavity and reaching the window reveal and then running down either side

Alternatively it could be the window was fitted badly and there was no vertical damp proof membrane installed at the time resulting in a situation where the plaster reveals are effectively connected to the outside brickwork -and that is a damp path.

Modern plasters are gypsum which is hygroscopic so they suck up any damp easily



Unfortunately it needs some exploratory work to find the cause -ie stripping off the plaster from the sides and head to see what is going on

if the problem is the lintel then it could there is no cavity tray just below the lintel -not an easy repair given you have a conservatory below

if the problem is lack of dpc on a the sides, then that can be resolved by removing plaster, putting in suitable dpc and replastering

I suppose we cant rule out condensation forming because of thermal bridging -IE the plaster reveals are getting very cold and condensation is forming -I guess you might be able to tell by when it happens: if its damp after rain then its not condensation