1. Main Tree Species of Solid Wood Flooring
Due to different materials, the hardness, natural color and texture of solid wood flooring are also quite different, as follows:
Oak oak (oak wood), sand pear, black ant (ebony), borneol incense (camphor tree), Diptera, Gamba pair, Baodi bean, camphor tree (ironwood), camphor tree, etc.
Medium: teak, Indocalamus (pineapple lattice), Miluo Shuang (balao), and fragrant dogwood (Ruxiang).
Soft: Fraxinus mandshurica, birch.
Light colors: Cyclobalanopsis (beech), birch, Japanese olive.
Middle colors: oak, Fraxinus mandshurica, Miluo Shuang, fragrant dogwood.
Dark colors: teak, tomato, heavy ant wood, fragrant winged bean and Pincado.
Coarse grains: teak, oak, croton and manchurian ash.
Fine lines: Cyclobalanopsis, birch.
2. Moisture content of solid wood floor
Wood contains three forms of water. One is water existing in cell cavities and intercellular spaces, that is, water existing in capillaries, which is called free water. The second is the water absorbed by the cell wall, which is called adsorbed water. The third is the water that constitutes the cell tissue, which is called chemical water.
When the moisture of wet wood evaporates, the first thing that is lost is free water. When free water evaporates and adsorbed water is still saturated, its moisture content is called fiber saturation point moisture content.
Fiber saturation point is the turning point of wood properties. Above the fiber saturation point, the strength of wood is constant and does not change with the change of water content. At the same time, there is no volume change of wood expansion and contraction. When the moisture content falls below the fiber saturation point, that is, the adsorbed water in the cell wall begins to evaporate, and the strength increases with the decrease of moisture content, and the phenomenon of wet swelling and dry shrinkage is also obvious. The moisture content of different wood fiber saturation points is about 22%~33%.
Humidity and temperature in different parts of nature are relatively stable in different seasons. Wood is in this relative temperature and humidity environment for a long time, and its moisture content will reach a relatively constant value. The moisture content at this time is called equilibrium moisture content (for example, the annual equilibrium moisture content in Shanghai is 4.6%).
The equilibrium moisture content of wood changes with the temperature and humidity of its environment. When the equilibrium moisture content is different from the ambient humidity, it tends to be close to the environment. This leads to the phenomenon of wet swelling and dry shrinkage of wood, which is a unique physical phenomenon of wood.
Wood is also an anisotropic body. The moisture content of wood in practical use is lower than the fiber saturation point, so the gain and loss of water is mainly the absorbed water of cell wall. Most wood cells grow vertically, and their expansion and contraction are perpendicular to the cell wall. As a floor, we can find that there is generally no expansion and contraction in the longitudinal direction, while the expansion and contraction rate in the width direction is generally 3% ~ 6% (referring to the change of wood moisture content below the fiber saturation point moisture content).
Therefore, it is very important to control the moisture content of the floor. Attention should be paid not only in production, but also in laying to prevent the floor from being deformed by moisture.
3. Dry balance treatment of solid wood floor
purpose
(1) reach the specified equilibrium moisture content suitable for the environmental characteristics of the use area.
(2) Eliminate the internal stress existing and produced in the process of wood growth and processing.
(3) Adjustment and recovery of deformation.
Because the annual equilibrium moisture content in Shanghai is 15.6%, the moisture content of floors used in Shanghai should be controlled between 10%- 14%.
process
(1) Natural drying takes about 30 ~ 40 days to make the water content reach about 30%.
(2) Artificial drying takes about 10 ~ 30 days to make the water content below 10%. At the same time, the pulp juice in wood is distilled, which balances the tissue of wood cell wall and makes the drying shrinkage tend to be stable and consistent.
(3) The curing treatment takes about 10 ~ 20 days. Through this process, the three purposes of wood drying are finally achieved.
Dry balance treatment is called heat treatment. The time of this treatment will vary with different materials, but it cannot be artificially shortened. There is a misunderstanding in sales that the heat-treated floor will never deform. In fact, this is impossible. No matter how it is treated, the moisture content of wood changes below the fiber saturation point, and it is inevitable that it will swell and shrink when wet.
4. Causes of deformation of solid wood floor
Generally speaking, the common phenomenon in use is that the floor is tiled or arched, which is caused by the floor being damp. The reasons why the floor is wet are roughly as follows:
(1) Moisture in the air (such as Huangmeitian).
(2) The floor is wet, and the keel is reinforced with cement.
(3) The keel and rough floor are too wet.
(4) Use water-based glue.
(5) The damp environment such as the first floor has not been specially moistureproof.
(6) The part where the stone floor meets the ground is not closed.
(7) Blisters (e.g. broken water pipes and backflow of balcony water). ).
In addition, the product itself and improper construction will also cause arching. For example, improper drying, insufficient curing, too low moisture content, too shallow back groove, insufficient expansion gap during construction, too tight laying and so on.
5. Laying and maintenance points of solid wood floor
(1) The floor slab shall be laid in the later stage of construction, and cross construction is not allowed. After laying, it should be polished and painted as soon as possible. In order to avoid soiling the floor or deformation due to moisture.
(2) Before laying, the floor should be unpacked and stacked at the laying site for 1 ~ 2 days to adapt to the environment and avoid expansion and contraction deformation after laying.
(3) Moisture-proof measures should be taken when laying, especially in damp places such as subfloor. Moisture-proof measures include coating moisture-proof paint, spreading moisture-proof film, and using bedding treasures.
(4) The keel shall be smooth and firm, and shall not be reinforced with cement. It is best to use expansion bolts and expansion nails.
(5) The keel should be made of wood with strong nail holding power, such as larch and Liu 'an. The moisture content of keel or wool floor should be close to the floor. Keel spacing should not be too large, generally not more than 30 cm. Both ends of the floor should be fixed on the keel, and no blank space should be left. Nails must be nailed on each keel. Do not use water-based glue.
(6) The floor should not be spread too tightly, with enough expansion joints (0.5 ~ 1.2 cm) around it, and it should not be spread too wide. In case of wide occasions, it should be cut off separately, and then pressed with copper bars for transition.
(7) Thorough isolation and moisture-proof measures should be taken at the junction of the floor and the stone floor such as the entrance hall, bathroom and kitchen.
(8) The floor color difference is inevitable. If the requirements for color difference are high, you can sort in advance and adopt the method of gradual change to reduce the visual sense of mutation.
(9) Avoid washing with water during use, avoid long-term sun exposure and continuous air conditioning direct blowing, and prevent the rain forest from colliding with hard objects at the window. In order to protect the floor, the paint surface can be waxed (from the perspective of protecting the floor, waxing is better than painting).