Rain penetration in rendered cavity wall

[brightbluesky]

The rear of my house is south facing on a hill and can take a lot of wind and rain, particularly in recent weather.
Since purchasing the house I have had outer walls rendered and double glazing fitted.
Despite these works rain is gaining access to the cavity walls and coming out above the back door in the conservatory and also now above the French windows in the lounge.
I have posted a number of photos depicting the rear of the house and where the rain is coming out.
I have employed a surveyor to pop around and he suggested rain possibly getting in due to drainage holes being blocked in the in double glazed units.
He also suggested getting the cavity wall trays replaced above both the conservatory rear door and above the French windows.
His view was that if the trays were put in place the water could no longer get into the house.
My query is:
With rendered walls and double glazed window, how is the rain getting in?
Will having cavity wall trays stop the water ingress? View media item 71854 View media item 71855 View media item 71854

 

[stuart45]

You have a band of brickwork where rain running down the wall could be getting in through the joints, especially the cross joints.

 

[brightbluesky]

Thanks Stuart, would cavity wall tray insertion and replacing brickwork and reprinting sort out the issue or what would you suggest?

 

[stuart45]

Cavity trays are designed to stop water entering above frames etc, so they could be the answer.
It depends if the rain is penetrating through the wall, and not the flashing.

 

[brightbluesky]

I have examined the two rows of brick with binoculars and there are indeed several missing pieces of mortar in the cross joints and some moss growing in others. There is also a slight ridge where the bricks protrude from the area directly below the rendered plaster work.
I think Stuart you may have identified the problem.
Now, do I just get the brickwork repointed and sealed or do I get new bricks inserted or do I need the cavity tray as well?
Any thoughts

 

[stuart45]

I would get the brickwork repointed first and see if that helps. It's not the best design to have a band of brickwork in a rendered wall though.