1.1.2 Materials properties:
Wooden houses are built in pine and cedar. Sometimes the foundation is of larch because it is firm and when put under water becomes as strong as iron. The upper part is constructed our of pine, because it helps to retain heat inside the house. Until the end of the last century, the interior of wooden houses was made out of clean logs.
For the long term durability of historical wooden buildings, constructors and users who deal with this subject have to know wood properties exactly. Wood is an organic, hygroscopic and anisotropic material. Its thermal, acoustic, electrical, mechanical, aesthetic, working, etc. properties are very suitable to use it is possible to build a comfortable house using only wooden products. With other materials, it is almost impossible.
· Low coefficient of thermal conductivity
· Low thermal expansion
· High Specific heat
Those properties lead to the internal temperature of the houses insulated in a simple way from the extremely low external temperature.
· Sound absorption
· Prevents echo and noise
· High resistance to electrical current (Dry wood)
· No static electricity
· Strength is quite high
· Decorative material
· Metals get rust, wood doesn’t. It’s very suitable to the humid zones like Irkutsk.
· Easy to repair and maintain
· Easy to execute, for that the old people of that place use it as main material of built
Also the wood has some problems with the durability, it must be treated to be protected from the deteriorations and diagnoses.