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I recently bought a 1930 semi detached property with cavity walls which had new DG windows and patio doors installed 7 years ago (10 year warranty still valid). I am having two separate but linked issues:

- Severe dampness and mould along right side of patio door (attached image). There is blown outside render at the right corner of the patio door which I assume is letting water in. The outerleaf bricks of the reveal are wet. I can fix the render issues easily but I am concerned that the patio door has not been fitted properly (is the patio door fitted too far forwards as it is in line with outside of the external leaf rather than inline with the outerleaf inner surface) and there is no vapour barrier between bricks and plaster which led to this problem

- The windows all seem to have been fitted in a similar fashion flush with the outside wall but dry lined reveals. The external wall therefore forms part of the internal window recesses. I get dampness every morning along the inner 2cm or so of the window recess presumably due to cold bridging (see picture where paint is peeling). Rest of inner recess is fine. This would be where the external leaf bricks lie. The dampness is patchy and varies between windows. It seems to be related to whether there is foam behind the plaster or not. Areas with foam behind them get much less condensation that those that do not. Those areas without foam are very drafty and you can feel a draft when you make a small hole in these areas.

My questions is how best to deal with these issues? I would like to get the job done properly. I have considered installing vertical DPC around the patio door (cold bridging still a problem?) and replastering. For the windows, I have thought about adding expanding foam to fill gaps, putting thermal wall paper (Wallrock) on top of the reveals or removing the window reveals and installing insulated plasterboard. The window reveals have approx 4-5cm depth around them.

Secondly, is it worth getting the window installers back to have a look? Have the windows and patio door been installed incorrectly? The company has very good reviews and I have confirmed 10 year warranty documentation.

Many thanks

Hi ap2048
This is a very common problem. I assume the originals were Timber windows and these have a wider section and so cover the outer brickwork skin. The replacement windows will be considerably narrow (as much as 20mm) and the installer has the choice of fitting flushish with the outer face, which then leaves a plaster repair inside over the inner edge of the outer skin. OR fitting the frame back to cover the inner edge of the outer skin which leaves a deeply set in window and probably a paint/seal line on the outer brickwork.
Suggest you hack off the plaster around your windows and fit a thick upvc trim to cover and insulate the outer brick.
Regards S

Thank you Stoneboy. Yes what you say makes sense and it seems like they have fitted it forward as you describe. I am not sure what the original doors were but is is a 1930s semi.

I was thinking of putting a DPC liner vertically over the exposed brick and plaster over but your idea of a UPVC trim sounds like a good one too. There is a approx one finger width deep gap between the brick work and patio door so are you suggesting filling that whole gap with a UPVC trim (might be tricky as the gap is uneven) or plastering over and covering UPVC trim?

Many thanks for your suggestions

Hi ap2048
If I am understanding you correctly you have a large “fitting tolerance” around your door. Fill this gap with expanding foam and fit a thick upvc section inside abutting the frame and to cover the inner corner of the outer skin.
Regards S

Thank you