Kirizuma-zukuri

What kirizuma-zukuri means

Kirizuma-zukuri is a Japanese roof form in which the surfaces slope in two directions only, falling away from a single ridge, so that each end of the building closes with a triangular gable.

The gable end is called the tsuma. Where the entrance is placed on that end, the building is described as tsumairi; where it sits on the long side parallel to the ridge, the term is hirairi. Two buildings can carry the same roof and read very differently depending on which face is treated as the front.

Compared with yosemune-zukuri, which slopes on all four sides, or irimoya-zukuri, which combines a gable above with hipped slopes below, the framing is simpler and there are fewer eaves corners to resolve. That is why storehouses, gates, fences, bell towers and shelter structures so often use it. Among shrine architecture, the shinmei, taisha and nagare forms all sit on gabled roofs.

The roofing material is a separate matter. Cypress bark, wood shingle, thatch, tile, copper sheet and sheet steel all work over a gabled frame. Japanese heritage records write the two together, as in kirizuma-zukuri dobanbuki, meaning a gabled roof covered in copper sheet. When you meet that pattern in a structural description, read it as roof shape followed by roofing material.

Telling it apart on site

Walk to the short end of the building. A triangular wall panel under the roof means kirizuma-zukuri. If the roof wraps around and no triangle appears, the form is hipped. If the triangle occupies only the upper part and the roof folds around below it, you are looking at irimoya-zukuri.

The gable end is where the carpentry shows itself: the bargeboards, and the hanging ornament known as gegyo that covers the ridge joint. How the gable wall is finished, and whether the rafter ends are left exposed, varies a great deal by period and region, which makes gable ends a useful thing to compare from one building to the next.