A Brief History of Fire
Posted by GLM on Jun 19, 2017 in Architecture, Building Surveying, Residential
What the Public Inquiry will conclude following the dreadful fire catastrophe at Grenfell Tower remains to be seen but it may be helpful to set it in a historical context.
The superstitious premodern view of fire, along with plague, was that it was a visitation from God on sinful humanity. It appeared to strike cities and towns at random and there was no obvious way to avoid it. Timber clad buildings crowded closely together in conditions of abysmal sanitation were understood to be the way that humans were obliged to live. Even the wealthy were driven to move from castle to castle with their entourages, when the stench of prolonged occupation became unbearable. The more fastidious Japanese could smell a European ship coming from miles away. Half-timbered cities like Edinburgh and Glasgow eventually cottoned onto the idea that cladding buildings in non-combustible stone made all the difference to their performance in a fire. The insides of such buildings remained as tinderboxes but at least the fire was, for the most part, contained.
The Great Fires of London and Edinburgh
Following the Great Fire of London in 1666, the disbenefits of combustible building envelopes had become more and more apparent. In the course of the succeeding centuries London and towns like Edinburgh and Glasgow started to harden up their buildings. Only stone built buildings from earlier times now survive except in cities like Chester, the Shambles in York and the little towns of Suffolk which, for a variety of reasons, have escaped upgrading. Some massive fires in multi-storey tenements like Edinburgh’s Great Fire of 1824, watched by Walter Scott, propelled action in Scotland ever further towards fire safety conscious urban planning, directed by the Deans of Guild.
Moving rapidly to the present time
In the 20th century fire safety moved further and further up the agenda. Wonderfully fire resistant asbestos came into universal use as part of a strategy to contain the spread of fire in buildings. The fire regulations focussed heavily on containment and means of escape. As the century progressed there was a growing sense that the life safety war on fire was beginning to be won. Some major fires stood out as exceptions such as the Summerland disaster on the Isle of Man in 1973 where a fire in a polycarbonate building killed around 53 people and injured another 80 and in 1992 the Windsor Castle fire drew attention to the vulnerability of priceless heritage assets.
America leads the way
In America the National Fire Protection Association (NFPA) had come to the conclusion that active fire protection in addition to passive fire protection could have major life safety benefits. This requires some explanation. Passive fire protection is the process whereby buildings became ever more fire resistant: the containment and means of escape strategy referred to previously. Active fire protection in the form of automatic sprinklers dates back to 1874 (an American invention). This approach was devised in response, typically, to warehouse fires where goods of great value were stored. Non-combustible construction had been taken about as far as it could go but there were still costly fires. Placing water valves above the seat of a potential fire, activated by a heat sensitive linkage, was seen as a means of suppressing fire at source and in time proved highly successful in stemming losses. Active fire suppression was, however, not generally seen in the U.K. as a reliable means of protecting human life and the fire regulations tended to ignore its benefits except in very large buildings like shopping malls. This attitude was reflected in the recommendations of the Bailey Report, following the Windsor Fire, which stopped short of recommending the fitting of sprinklers in the reinstated building even though sprinklers, or in all probability, the activation of a single sprinkler head, would have suppressed the fire and prevented the disaster in the first place.
By the 1990s a growing body of opinion was looking to America for inspiration in the matter of Fire Safety. Those responsible for the buildings of the Library of Congress which house a national treasure trove of archival material, came to appreciate that only sprinklers would save the collections in the event of fire. Scotland was relatively quick on the uptake. Duff House, a fine mansion housing an offshoot of the National Galleries of Scotland, was retrofitted with sprinklers by Historic Scotland in the early 1990s. The National Library of Scotland and adjoining buildings followed suit. Newhailes House and Broughton House were fitted with sprinklers by the National Trust for Scotland and many others have since been delivered from the threat of catastrophic fire. However it wasn’t just in relation to the protection of historic building fabric and valuable contents that fire suppression came to be seen as being of value. Increasingly Fire Brigades have promoted sprinklers for their life safety benefits, particularly in tall buildings where means of escape can easily be compromised.
At this stage it seems very probable that the thermal performance upgrade to Grenfell Tower was heavily implicated in the disaster. Improving the thermal performance of a building on the outside is, of course, the right place to do it because it keeps the main fabric of the walls inside the thermal envelope and avoids lack of continuity at floors and dividing walls. Overcladding with insulation has become the preferred option for improving the thermal resistance of existing buildings. This can very easily take us back to medieval standards of combustibility and fire spread if rigorous preventative measures are not introduced. These could include having a professional “lead consultant” in charge of the design and contract administration of this kind of project instead of the cost driven passion for contractor-led “design and build”.
As a practice GLM has been involved in many projects where fire safety has been a key focus. We are currently restoring a magnificent Category A Listed castle where, on our recommendation, but not as a requirement of the authorities, sprinklers have been installed, very discretely. This is one of a string of projects where we have been involved in the retrofitting of sprinklers into historic buildings. If it can be done successfully in buildings like these, we would argue, it can be done anywhere. In another case, we were responsible for a project that dealt with a complex problem involving deficient firestopping in row of townhouses that had been converted into a hotel. Currently we are the lead consultant on a project that is dealing with similar problems in a large laboratory building. At Grenfell Tower it appears probable that the fire started inside. If so sprinklers would almost certainly have halted it in its tracks. However, it is also possible to fit a drenching system externally on a building and this may well be worth evaluating as an option if other buildings turn out to be compromised in a similar manner.
In the wake of the Grenfell Tower disaster it seems likely that the large number of multi storey buildings that have been overclad with insulation over the past 20 or 30 years will now have to be carefully examined in detail to determine how much of a hazard they present to their occupants. An examination of these buildings could also have the additional benefit of determining the thermal performance level that they were upgraded to. Often this information is lost in the mists of time and policy in relation to climate change and fuel poverty is hampered by a lack of hard data.
Director, Chartered Building Surveyor