Fire resistance of wooden houses
Poor fire resistance is nothing but a myth when it comes to a laminated timber. In Finland people build almost everything of wood – high-rise buildings, offices, hotels, not to forget saunas. For the record, its citizens care a lot about their safety. Many Suomi regions are fully wooden – there are even some houses aged more than 100 years!
What is more, Finnish also build schools and kinder gardens from wood, designing terraces for sleeping time. You’ll never guess… There are even gas stations! All because the tree saves you in case of fire, not kill you. No need to feel tricky – we all have such knowledge thanks to long-term studies of the peculiarities of this material to make it beneficial for the society.
Consider yourself how the timber copes with three main hazards under fire conditions.
1) The main danger under any fire is the collapse of the beams.
The thing is that the metal at high temperatures deforms rapidly and loses up to 80% of its strength. Concrete, stones and bricks under intensive heat impact reduce the load-carrying capacity, besides, when the water hits on, the surface layers are being destroyed and the fire gets inside the building.
Profiled beam does not burn in the fire, yet becomes charred; in addition, beam section is being reduced which means the material retains its strength longer. That is the reason why in Europe, when building multi-span buildings, they use wood and not metal.
2) Walls burn-up
Fires usually arise not from the ignition of walls, but from the getting curtains, wallpapers, furniture, etc., on fire. Think of how you light a fire: you can’t light up a beam. You can’t even light up stove woods without paper or small sticks.
The tests have shown that glued laminated timber is able to withstand 45 minutes of open fire exposure until it ignites itself – this is all due to its massive structure.
You can find some video on the Internet where people try to set glulam on fire with a gas lamp, in which the temperature of fire reaches 13000 degrees. In practice, during fire the temperature reaches 800-900 degrees only in the epicentre. The moment the source of fire is eliminated, the timber starts to fade.
Even if you spill the gasoline on the wall, the result will be the same: the gasoline will burn down but not the walls. Walls made of glued laminated tinder are monolithic and the material itself is very resistant to any kind of deformations. Therefore, there is no place for the fire to «catch».
3) Smoke poisoning
It is well known that during fire many people die not directly from the fire but from suffocation caused by burning of synthetic materials, which are contained in building and finishing materials as well as in fire retardant treatment. Lumi Polar does not work a surface of the beam as it loses its natural features and can turn into poisonous. Our houses built from high quality timber, which is professionally processed and dries, do not require any special means of protection. Our houses are 100% eco-friendly as we use Swiss ecological glue without phenols and as we do not use any synthetic materials in our construction.
Some numbers to consider
According to the Finnish standards SFS-EN 1361-1, fire resistance requirements of the supporting structures - R30, and for fire barriers - L30. In accordance with the tests, these requirements are met even by a beam with a thickness of 92 mm, and a beam of 138 mm has a fire resistance class R60 – it withstands open fire for an hour or more!
Instead-of-conclusion
To state that wooden houses do not burn at all would be not fair. Saying that wooden houses are super exposed to the fire also would not be fair. It is all completely wrong. In accordance with Russian regulations, waiting time for the fire brigade is 10 minutes in the city and 20 minutes at the countryside. High quality, well-dried timber significantly «jumps over» these standards and is able to withstand fire much longer than any other construction material.
