Structural plywood is used for floors, walls, roofs, and other structural components of residential buildings. At Shimane Plywood, products are manufactured in thicknesses ranging from 5 mm to 30 mm, with the principal panel sizes being 3 shaku × 6 shaku (910 mm × 1,820 mm) and 1 m × 2 m. Product specifications are established under JAS (Japanese Agricultural Standards). Shimane Plywood uses three wood species: Japanese cedar, Japanese cypress, and Douglas fir. JAS classifications include strength grades (Grade 1 and Grade 2), formaldehyde emission levels, and adhesive durability classifications (Special Type and Type 1). The durability of structural plywood depends on the environmental conditions in which it is used; therefore, no clearly defined warranty period exists. However, the statutory defect liability period is 10 years, and many major housing manufacturers provide warranties of 20 to 30 years.