One masonry shape may have several names. Some dimensions also look similar but are measured in different directions. These definitions help you read the drawing, enter measurements and understand the brick layout.
Brick faces and dimensions
Header: the short face of a brick. Stretcher: the long face. Length, width and height: the three dimensions of a whole brick. Depth in a drawing: the direction through the masonry, which depends on brick orientation. A standing or lying brick describes orientation, not a different material.
Joints and repeating dimensions
Bed joint: the horizontal joint between courses. Head joint, also called a perp joint: the joint between adjacent bricks. Course gauge: brick height plus a bed joint in a repeated module. Header module: header width plus a head joint. Brick layout or division: the arrangement of whole and cut pieces with their joints within the available space.
Parts of an arch
Clear opening: the gap in the masonry. Span: the straight distance between springings. Springing: where the arch starts. Rise: height of the inner crown above the springing line. Intrados and extrados: inner and outer boundaries of the arch ring. Voussoir: an arch wedge or arch unit. Keystone: a closing unit at the crown. Setting-out centre: the reference point used to draw the specified curves or division lines.
Shape names and their drawings
A jack arch is also called a flat arch. A semicircular arch is a half circle; a segmental arch uses a circular segment. Pointed arches are associated with Gothic forms. Basket-handle arches combine circular curves, while an elliptical arch follows an ellipse. A Tudor arch is four-centred. Dutch gable weaving describes special brickwork along a sloping gable edge. Open the linked shape pages to compare their geometry.