Just as at an angle or quoin in brickwork, bricks specially cut have to be used to complete, or close, the 1/4 B overlap caused by bonding, so at jambs special closer bricks B wide on face have to be used.
Provided that the outer reveal is 1/4 B wide, the following basic rules will apply irrespective of the sort of bond used or the thickness of the wall. If the rebate is B deep the bonding at one jamb will be arranged as illustrated in Fig. 88. In every other course of bricks a header face and then a closer of 1/4 B wide face must appear at the jamb or angle of the opening. To do this and at the same time to form the 1/4 B deep rebate and to avoid vertical joints continuously up the wall, two cut bricks have to be used.
These are a bevelled bat (a ‘bat’ is any cut part of a brick), which is shaped as shown in Fig. 88, and a king closer, which is illustrated in Fig. 88. Neither of these bricks is made specially to the shape and size shown, but is cut from whole bricks on the site.
In the course above and below, two other cut bricks, called bevelled closers, should be used behind the stretcher brick. These two bricks are used so as to avoid a vertical joint. Figure 88 shows a view of a bevelled closer.
Fig. 88 Bonding at rebated jambs.
Where the rebate is 1/2 B deep the bonding is less complicated. An arrangement of half bats as quoin header and two bevelled closers in alternate courses for English bond and half bats and king closers in alternate courses for Flemish bond is used.