Ridge

Rules that use the word

Raise the ridge by a third of the depth. For a great hall, measure the distance between the front and back eave purlins and raise the ridge purlin above them by one third of it; for lesser halls, by about a quarter.

Depress each purlin: 1/10, 1/20, 1/40…. Draw a straight line from the ridge purlin to the eave purlin and lower the first purlin below the ridge from it by one tenth of the rise; from that point draw a new line to the eave purlin and lower the next purlin by one twentieth; continue, halving each time.

Qing jǔjià: five-tenths at the eaves, nine at the ridge. Give each rafter span a fixed slope, increasing from the eaves to the ridge: half-pitch (5 jǔ) for the eave span, then about 6½ or 7, 7½, and 9 tenths for the span below the ridge.

The ridge-and-furrow roof. Glaze a roof in a series of small ridges and valleys, the panes set at an angle on light sash bars, so that the low sun of morning and evening strikes the glass more squarely, the roof is stiffened by its folds, and the rain runs into gutters in the furrows.

The Crystal Palace grid of 24 feet. Build on a single grid of 24 feet, set by the 8-foot spacing of the roof ridges and the size of the largest pane of glass, so that every column, girder, sash bar and pane is one of a few standard parts that can be made by machine, delivered and bolted together in any number.

Shinmei-zukuri: the style of Ise. Build the sanctuary of unpainted cypress on posts set directly in the ground, with a raised floor and veranda, a straight thatched gable roof entered on the long side, crossed finials (chigi) and ridge billets (katsuogi), and a free-standing post at each gable carrying the ridge.

Where it appears in the book

In the chapters Vaults, The Roof, Frame and Skin, China, Japan and Korea, Gardens and Landscape.

A feature of Chinese architecture.

Nearby in the glossary

Ressaut · Rib · Rib vault · Ribbon window · Ridge rib · Ridge-and-furrow · Rill · Rise