Japanese Interlocking Wave Eaves J-Tile Smoke Gray Ceramic Roof Tile for Asian Style Roofs Japan Tea House The J‑type roof tile, known in Japanese as Jigata-gawara (J形瓦), represents a harmonious fusion of function and aesthetics that has defined Japanese architecture for over four centuries. Its distinctive wave‑like profile is not merely decorative—it serves to break up wind flow, reduce rain noise, and channel water efficiently. Our Smoke Gray Ceramic J‑Tile continues this