BUILDING BOARD

摘要

The present invention provides a building board having a flat shape in which concave parts and convex parts are formed on a surface thereof, wherein the concave parts and the convex parts are arranged alternately and extend in the same direction such that widths thereof in a direction, in which the concave parts and the convex parts are alternately arranged, change gradually. It is preferred that the concave parts and the convex parts be arranged such that the widths of the concave parts gradually increase or decrease and the widths of the convex parts gradually decrease or increase in the direction in which the concave parts and the convex parts are alternately arranged.