Safe and diverse design features for the ceiling as well.
The ceiling can be classified as a "specific ceiling" under the Ministry of Land, Infrastructure, Transport and Tourism Notification No. 771, as the mass of the ceiling surface area construction material is 2 kg/m² or less. In addition to being lightweight, the ceiling material has low water absorption and does not experience degradation of thermal insulation performance over time. The standard sizes are 910mm × 910mm and 910mm × 1,820mm, but size modifications to meet customer needs are possible. The surface finish is available not only in the standard off-white specification but also from a wide variety of material and color options. The ceiling material is certified as non-combustible (Ministry of Land, Infrastructure, Transport and Tourism Certification: NM-4712(1)).