Missing cavity barriers/fire socks

[tinysue180]

Good morning.
After some advice with our current situation!
I purchased a timber frame new build from a local builder. He and his partner had never built timber frame before but decided to undertake 5 new houses! During the first winter we noticed water ingress on the window reveals. The builder blamed condensation which is not covered on our NHBC warranty.
The window manufacturer thought that the windows weren't sealed properly and drilled through the frames! This has now caused excessive condensation on the aluminium frames as the thermal break could be compromised.

When one of the window fitters commented that he thought that the windows didn't look in the correct place...we started our own investigation!!  Bricks were removed which showed no cavity closures and the aluminium window sat in the wrong place in the cavity. (we have spoken to the timber frame manufacturer and he has confirmed what SHOULD be there).
After a claim with NHBC, the builders have been told that they need to put fire socks around windows and doors. Our concern is...how are they going to fit these?
They have suggested removing bricks top and bottom and pulling the socks  through.  Any advice from anybody on here?
Not a Persimmon home this time but just as bad!!!

[New Home Expert]

Oh dear.  You could have a home with a whole lot of defects.

Standard practice is that at window and door openings a 50 x 47 sawn timber batten is used to close the (50mm) cavity. This batten then has dpc fixed to it to prevent water coming through to the inside and the timber frame.  AS you rightly say every opening should have also cavity closing fire stopping "socks" around the timber closers.  The only way to retro fit is is to take out bricks either side. It could be possible to pull it up from either end. 

However, you must ask yourself whether the fire sock cavity barriers are above and below the first floor and most important at eaves level.  I would suggest a endoscope camera survey to ascertain  this.  IF you live in a semi or terrace this is critically  important to prevent spread of fire from other properties.

You should also check for weep vents which act as cavity ventilation for the timber frame above and below the floor and at dpc level. Another thing to check is a gap under window and doors (sealed with special mastic) which allows for the timber to settle as it dries out under load from the roof and drylining.  25mm under eaves soffit board  and 12mm under ground floor windows.

As you say at least it isn't a Persimmon Home!
Do the other four homes have this defect? I suspect the answer is yes!