 The Palace of Westminster is home to one of the busiest parliamentary institutions in the world. Thousands of people work here and visit every day. And millions of tourists are drawn to its iconic splendour. Completed in the mid-1800s, many of the palace's features have never undergone major renovation. So what's being done to tackle any problems, not only to ensure the palace continues to function as a working building, but also to preserve its unique heritage for future generations? In this video, we look at the windows of the palace. There are 3,000 windows, from basic casements in rooms and corridors, to the ornate glass panels that allow light to flood into the many hallways and chambers. This fast expanse of glass, much of it set in bronze framework, no longer provides effective weather resistance and generates significant heat loss from the palace. While a range of measures to reduce CO2 emissions are being implemented, the palace's status as part of a World Heritage Site and Grade 1 listed building means that many energy-saving solutions are not appropriate. However, making windows weathertight across the entire palace will go a significant way towards reducing heat loss and running costs. You can see from here the significance of the windows in these building elevations of the Palace of Westminster, not one of them actually closes properly. Every single one of these windows needs to be taken out and overhauled in order that it stops letting heat out of the building and letting the water in. These windows inevitably have deteriorated over time far more quickly than we can maintain or repair them. I can feel here the draft coming through the bottoms of the windows. This is a problem throughout the 3,000 windows all over the palace. If we can overhaul all of these windows and draft proof them, we will go a very, very long way to reducing the carbon footprint of the whole palace. Of course, that means saving an awful lot on heating costs. Every single window needs to be surveyed in detail by specialist contractors taken to a workshop, overhauled some of its components replaced, brought back and refixed into the stonework. Apart from that, we have the problems with access, physically getting to the windows in order to remove them. Some of them are in very sensitive places where we can't be working during parliamentary sitting times. And so the whole of the programme of window repair will at the current rate take very many years to complete. If we don't look after this building, if we don't do something about the state of the stonework, the timber, the windows, it will not be here for future generations. Quite apart from the fact, it may not be fit for purpose very soon for the use for which it was designed. To find out more, please watch the other videos in this series.