The Building Conservation Directory 2021

144 T H E B U I L D I N G C O N S E R VAT I O N D I R E C T O R Y 2 0 2 1 C AT H E D R A L C O MM U N I C AT I O N S AWNINGS and CANOPIES Learning from the past ROBYN PENDER W E ARE in lockdown London: it is pouring with rain and the queue snaking along the footpath, waiting patiently to enter the supermarket, shelters gratefully under the canopies put out by the cafés and small shops. There are gaps in the queue where shopfronts have been modernised and have lost their awnings. In these gaps one or two people huddle under umbrellas, but most prefer to wait under the kindly shelter of the awnings, idly reading menus and window shopping. In a small office overhead, the manager (who has been reading the government health bulletins urging offices to ensure plenty of natural ventilation) is trying to prop open the modern casement windows in a way that does not let in the rain and wind. Her neighbour is luckier: his windows still have the original sliding sashes and although these have been neglected and lost their sash-cords long ago, it is still possible to wedge them open at the bottom, and a little at the top. That has made things in that office much less steamy, but the gap at the top is letting in rain and may have to be shut. At the top of the frame on the outside is a painted metal panel that helps a little and the manager wonders why it isn’t larger, to keep out more of the rain. Yesterday it was sunny, but neither office fared much better: the winter sun came straight in through the glass in the mid-afternoon, instantly overheating all the staff, and making it impossible for them to read their computer screens. But the metal panel is not in fact a rain guard: it is actually an awning hood, and it shows that the upstairs windows, too, once had canvas awnings. When these fell out of fashion in the middle of the 20th century, their mechanisms were removed. It is often only the protective hood, and perhaps the cleats on the frame once used to fasten the awning cords, that remain from what was once an all but ubiquitous fitting. It often surprises people when they look at early photographs of cities like London to realise just how many windows did have awnings – even on buildings such as Buckingham Palace. But a visitor from a country where the use of awnings has never stopped, such as Holland or Sweden, might be still more surprised by their disappearance in Britain: because awnings really are an unparalleled way of dealing with the problems of glass windows. They prevent the sun overheating the glass, cut direct solar radiation (with all its associated problems of glare, overheating and UV damage), and they allow windows to be kept ajar for ventilation in all but the most-windy conditions. The need for awnings must have become obvious as soon as glass became cheap enough to allow for large areas of glazing. The Georgians quickly discovered that once a building envelope incorporates sizable areas of glass, overheating becomes a greater concern than cooling, even in the winter and in a cold climate such as the UK. As well as causing the occupants immediate discomfort from heat and radiation, the sunlight also causes fading and other degradation of organic materials such as timber and fabric. In contemporary paintings and prints we can see that plain cloth awnings appear on windows soon after the invention of the vertically sliding sash, and from these simple beginnings the awning developed quickly in sophistication. The Victorians in particular A Georgian door in London with a surviving awning, which not only stopped sun penetrating the transom light, but also served as rain protection (Photo: Robyn Pender) proved themselves to be brilliant innovators, coming up with a myriad of special forms that worked closely with sash windows to give occupants fine control not just over light levels, but also over ventilation. As contemporary advertisements make clear, many awnings were specifically designed to encourage through- draughts, even when they had been completely lowered to protect the window from the sun or rain. With the right awnings in place, even in the rainiest summer weather windows could be opened top and bottom to flush heat from the building. Awnings also helped retain warmth in winter.1 There were even portable awnings that could be carried with you on your travels, to improve the conditions in your room should you be staying in hotels or guest houses that did not already have their own. All could be