Updated on July 7, 2018
How Safe Is A Timber Building In A Fire?
Often an emotive subject and in need of logic. Whilst you know that the timber buildings are not only attractive, but are also sustainable, economical and provide fast construction alternatives; the assumption can be that because we use wood for fuel it must therefore burn easily! However, this is not strictly accurate. In fact, wood is selected as fuel since it burns little by little and at an estimated rate and these are generally the same qualities which can make it a safe construction product in the event of fire and should provide you with confidence in your wooden building. mobile field shelters
The “charring rate” of a wood framework means the time needed for the wood to be burnt through. This kind of can be calculated to determine the safety of a building or the length of time it will take to burn and weaken it is structural integrity: a calculations of the “degree of redundancy” in the composition. As a result of the thermal properties of your timber building this can show that the wood log will char on one side yet not even be warm simply a few millimetres inside the log. These qualities clashes with the unpredictable characteristics of other structural products such as steel; which heat up more consistently and offer rise to growth and loss of durability over the whole section, or masonry which fractures and spalls. Fire-fighters choose to enter an using up building made of hardwood since they are better able to estimate how long they are able to remain safely and securely inside. Timber will not fail considerably like, for instance, reinforced concrete.
Several timbers char at different rates largely depending on their density with a denser hardwoods charring at only 12-15 mm per half an hour. Possibly low density timbers will take 30 minutes to burn through to a 25mm thickness which immediately indicates the slow burn up rate expected of an MPL wood building: which is constructed from no less than 68mm solid log – this will ensure that the wooden building will retain structural integrity for over 1 hour of publicity to fire.
Structural timbers need to meet criteria BS5268-2 which offer an exhaustion rate of 20mm in 30 minutes.
However, it is vital to note that all buildings whether constructed from timber or brick and block must abide by building regulations and this includes fire prevention and hold.
Although a timber building takes a very long time to burn through, the surface can allow a flame to travel to a more quickly combustible material such as soft furnishings. For this reason it can be recommended that an additional Fire safeguard treatment is employed in areas where there is very best risk i. e.: near boundaries (externally) or in hallway/vestibule areas (internally).
Therapies such as NON-COM, available from specialists as Posture Chemicals, can be applied off-site to external metal cladding materials and definitely will result is a certified Class To protection. Similarly internal treatments such as Nullifire, that can be applied on site in only one day, can ensure that Class O safeguard exists where required. To comply; materials must have a Class 1 Area Spread of Flame and low fire propagation index in accordance with BALONEY 476 Part 6. Many timbers can achieve School O where treated with a suitable fire-resistant treatment.
These treatments not only keep you safe in the event of fireplace – but can also prevent ignition and reduce the speed of heat release, all of which retains the structural integrity of wooden building for much longer.