Plywood used in areas of buildings where strength is required.

Structural plywood is plywood that is used in places where it is necessary for the structural strength of the building.
It is mainly used as a base material for walls, floors, and roofs in wooden buildings. By using structural plywood to build load-bearing walls and floors, it is possible to dramatically increase earthquake and wind resistance.

Quality is defined by the Japanese Agricultural Standards.

Since it is used as a base material for buildings, the standards for strength grade and quality of the board surface are specified by JAS (Japanese Agricultural Standards).
These days, there are many domestically produced products that are made from domestic softwood lumber. (Abies sachalinensis, larch, cedar, etc.)
In the past, many imported products made of lauan were used, but now domestic softwood plantation trees and thinned wood are being used.
Softwood structural plywood produced in Japan is available in a wide range of sizes.

Used as a base for walls and floors where strength is required

It is used as a base for walls and floors that need to be strong for the structure of the building.
Recently, there has been an increase in the number of cases where domestically produced softwood structural plywood is used as a surface for design purposes.
However, it will be a plywood with a lot of loose knots and uneven colors, so it is suitable only if you prefer a messy or rough appearance.