I was entirely satisfied with the installation, to the point that I recommended this company to a neighbour of mine. The windows have been repainted every 5 years since installation with microporous paint, as recommended. In August 2012, I identified wet rot in the window frames. A specialist in Listed building repair work investigated and, coincidentally, cracks appeared in the glazing panels of 9 of the windows. His report was submitted to the company who have shown absolutely no interest, blaming me for causing the problem by failing to carry out adequate maintenance. Subsequent investigations reveal:
1) Nails securing the tenon joints had corroded, leaving timber in the area in poor condition.
2) The angle at which some of the windows were installed in this old property had compromised the efficiency of the sills.
3) The tight margin between sill and bottom rail created a water trap.
4) The draft control strips in each window allowed moisture to be retained which soaked into the frames.
5) The glass had been fitted so snugly into the frames that any movement of the house was likely to cause stress fractures.
This has turned out to be a disaster and I am seeking legal advice.