At present, there are three kinds of solid wood flooring and two kinds of multi-storey floors.
The three-layer solid wood composite floor takes Beauty House as an example. Its surface is made of high-quality and precious wood sheets, and its middle and bottom are made of fast-growing wood by hot pressing with glue. The thickness of the surface layer is about 4 mm, the core layer is about 8-9 mm, the bottom layer is about 2 mm, and the total thickness is generally 14-15 mm.
The multi-layer solid wood composite floor is made of multi-layer plywood as the base material and the surface layer is hardwood chips mosaic board or planing veneer by hot pressing with glue. The number of plywood layers must be single, usually three or five layers. The surface layer, such as hardwood chips, is usually 1.2 mm thick, and the plank is 0.2-0.8 mm. The total thickness is usually no more than 12 mm.
Solid wood composite flooring has the advantages of natural and beautiful wood grain, comfortable feet, sound insulation and heat preservation. At the same time, it overcomes the disadvantage of easy deformation of solid wood flooring (each layer of wood fiber is perpendicular to each other, which disperses the deformation and stress). The size is large and the laying is convenient.
The disadvantage is that if the bonding quality is poor, there will be degumming. In addition, due to the thinner surface (especially multilayer), attention must be paid to maintenance. So there are restrictions on using occasions.
The amount of formaldehyde released from solid wood flooring is a very important index when it is glued together. The state has mandatory standards for this, namely, GB18580-2001 < indoor decoration materials wood-based panels and their products formaldehyde emission limit. The standard stipulates that the solid wood composite floor must meet the E1 grade requirement (formaldehyde emission < 1.5mg/L) and be clearly stated on the product mark.