04/11/2016
Trends in modern building are developing at a rapid pace. Construction techniques to contain fires and limit damage allied to new trends such as the resurgence in the demand for wooden structures have flipped traditional thinking of how to build fire-safe buildings on its head.
The first priority of developers and builders is to ensure compliance with the national Building Regulations which is aimed at protecting the safety of occupants and preserving life. However, should a fire occur, many structures built to older regulations are often irrecoverably damaged, leaving owners and insurers to pick up the pieces whilst the tenants move on.
New developments are not only looking at saving as much of the building as possible, but also moving towards using renewable material.
Can modern buildings be both fire-safe and environmentally friendly? It appears they can.
Fire Break Floors
Lessening building damage should a fire occur has numerous advantages. The more of a building that can be saved in the event of a catastrophic fire the less environmental impact will occur as a result. In addition, insurers also face less risk, meaning that premiums can be kept at a reasonable rate.
Fire break floors are one method engineers and architects are using to completely isolate a fire in one part of a building, to the point the rest of the structure could, in theory, continue to operate as normal if a blaze broke out.
The taller the building the more important fire break floors become. In an ideal situation, an entire floor of a building can be consumed by fire without it spreading to other parts of the building and causing further structural damage.
Fire break floors are a step above compartmentalisation. By using plant floors, which are unoccupied and have low fire load, it allows for each sector of a building to operate almost independently, minimising the vertical connections between the different parts of the structure, other than the fire resistant stair, lift and service shafts.
An example of this is the 306 metre Shard in London, which is subdivided by plant floors at three intermediate heights, separating the various functions of the mixed-use tower: public viewing galleries, private residential floors, hotel / restaurant and offices at the base. This has allowed the fire risk in each part of the building and a range of possible intensities and durations of fire, to be considered independently, resulting in different structural fire engineering solutions being devised for each zone to minimise the damage should a fire break out.
A wooden renaissance
Over the last five years there has been an explosion in the construction of wooden towers, including the 10-story, 104-feet-high Forte residential block was erected overlooking Melbourne's Victoria Harbour.
It was the world's tallest timber building until The Treet in Central Bergen, Norway, stole that title in 2014, with an extra four stories.
And 2015 saw the opening of the Cube, a 109-feet-high apartment block in London's Shoreditch, which became, "the tallest cross-laminated timber structure in Europe", according to its developers.
In April this year, PLP Architecture and researchers from Cambridge University revealed the concept for a 300-metre tall, timber-framed building to be added to the Barbican housing estate, to be known as the Oakwood Tower.
Not only is timber seen as a way to speed up construction and reduce carbon emissions, it is a renewable energy source - a huge plus in today’s increasingly environmentally conscious society.
New ultra-strong timbers are driving the trend, such as cross-laminated timber. This involves thin layers of wood placed across one another at right angles and laminated with fire-resistant glue to create a stronger weave. Bamboo, which has been used for centuries in Asia is also being developed to create a strong, sustainable building material.
But there is one burning question - is wood fire-safe?
According to extensive research, the answer is yes. Surprisingly, has been found to be more fire resistant than regular steel and concreate constructed buildings.
Dr. Michael Ramage, of the Center for Natural Material Innovation at Cambridge University, recently told CNN,
“"There is a huge perception problem [regarding wood]. Timber doesn't burn in the way the public imagines.
"The great fires of London and Chicago were both sparked by very small pieces of wood. Very big pieces of wood are quite hard to set on fire -- they aren't kindling material."
He adds, “Because wood burns predictably, fire engineers can calculate how large a block of wood is needed to provide a protective layer to sustain a building for a certain period of time.”
"All buildings over a certain size need to have sprinklers and active fire suppression systems -- irrelevant of whether it's wood, concrete or steel".
Concluding comments
Research into fire-resistant building materials and further developments in wood can help not only improve chances of saving the people and much of the building itself during a catastrophic fire, both the environment and the economy benefit as well.
Fisher Scoggins Waters are a London based law firm who are experts in construction, manufacturing and engineering law. If you would like more information about making an insurance claim or engaging an emergency response following a fire or other disaster, please phone us on 0207 993 6960.