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Brick bond
Brick bond is the arrangement of bricks in the masonry wall where in each horizontal layer and in
vertical layers that are placed on top of one another there is rhythmic recurrence of the long edges and
of the half-narrower ends. Bricks having been laid in the wall with the longest edge are called stretchers,
but those placed crosswise are called headers.
Brick bond has a practical as well as decorative meaning. In order to ensure the stability of brickwork,
as well as load carrying capacity and durability to mechanic impact, it was necessary to lay headers and
stretchers interchangeably. The external walls of medieval brick masonry buildings were one or several
metres thick. The inner loose rubble filling consisted of irregular or broken building materials that were
thrown into a rich mass of lime mortar, but bricks were used in hollow revetment walls of both sides.
The choice of bond not only determined the number of required building elements but also ensured that
the revetment sufficiently strongly meshed with the filling in the middle.
If the revetment is laid only from stretchers it can separate from the filling much easier than in the
case when stretchers are interchanged with headers thus ensuring meshing. Moreover, red bricks with
carefully made light joints, in a regular bond, created a rhythmic network on the smooth plane of a wall –
a decorative ornament and simple geometric figures. Some researchers hold the opinion that the
rhythmical arrangement of bricks in bonds where one or two stretchers are regularly interchanged with
one header was associated in the Middle Ages with scholastic comprehension of geometry and with
making divine of this teaching that is applied in construction (Holst 2008, 176).
In medieval buildings a regular bond was typically chosen for façades and for the walls of the
interior that were not covered by plastering. Elsewhere – especially in the basements or back walls of
buildings – the rhythm of brick bond is not consistently taken into account, since sometimes for the
purpose of saving materials stretchers were used more, or non-standard pieces were laid in.
In the 13th–17th centuries, in the territory of Latvia, three main brick bond patterns were known –
Wendish, Gothic and Block bond (Fig. 11; Erdmanis 1989, 154–156). The designations have been taken
over from German literature where the following designations are used: wendischer, 2:1, gotischer, 1:1,
Block-, Kreuzverband (Herrmann 2007, 101, 113; Koepf 1999, 317–319). Since each bond pattern was
applied for a not very long time period and they replaced each other, researchers of medieval buildings
use them for approximate dating of brick masonry walls.
The Wendish bond appeared in Europe in Romanesque buildings at the end of the 12th century
(Holst 2008, 176). It is characterised by brick layout when in each layer a header followed two stretchers.
The bond is called regular if vertical joints are distributed evenly and after a definite number of rows
they are on the same line. The headers then are distributed in diagonal zones or are placed just on top
of one another in every even-numbered row. In irregular bond the masons did not pay attention to the
arrangement of vertical joints. In Latvia’s territory the Wendish bond started to be applied in the first
decades of the 13th century, but it could be encountered even in the 15th century (Erdmanis 1989, 156).
Regular Wendish bond was chosen, for example, for the masonry of the apse of the Dom Church in Riga
built in the first half of the 13th century.